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* [PATCH v3 0/10] KVM: x86: allow compiling out SMM support
@ 2022-10-27 16:49 Paolo Bonzini
  2022-10-27 16:49 ` [PATCH 01/10] KVM: x86: start moving SMM-related functions to new files Paolo Bonzini
                   ` (9 more replies)
  0 siblings, 10 replies; 12+ messages in thread
From: Paolo Bonzini @ 2022-10-27 16:49 UTC (permalink / raw)
  To: linux-kernel, kvm; +Cc: mlevitsk, seanjc

Some users of KVM implement the UEFI variable store through a paravirtual device
that does not require the "SMM lockbox" component of edk2; allow them to
compile out system management mode, which is not a full implementation
especially in how it interacts with nested virtualization.

In order to limit the number and especially the size of the #ifdefs,
the first 4 patches move most SMM code to a completely new file in
arch/x86/kvm.  Patch 5 is the main change to introduce the Kconfig
symbol and key smm.c's compilation off it; patches 6-10 instead
eliminate other bits of SMM code that remain outside smm.c.

Paolo

v2->v3: remove kvm_smm_changed stub as well as more code in KVM_GET_VCPU_EVENTS
	leave kvm_apic_init_sipi_allowed inline
	change placement Kconfig to generate the right menu hierarchy

Paolo Bonzini (9):
  KVM: x86: start moving SMM-related functions to new files
  KVM: x86: move SMM entry to a new file
  KVM: x86: move SMM exit to a new file
  KVM: x86: do not go through ctxt->ops when emulating rsm
  KVM: allow compiling out SMM support
  KVM: x86: compile out vendor-specific code if SMM is disabled
  KVM: x86: remove SMRAM address space if SMM is not supported
  KVM: x86: do not define KVM_REQ_SMI if SMM disabled
  KVM: zero output of KVM_GET_VCPU_EVENTS before filling in the struct

Sean Christopherson (1):
  KVM: x86: do not define SMM-related constants if SMM disabled

 arch/x86/include/asm/kvm-x86-ops.h            |   2 +
 arch/x86/include/asm/kvm_host.h               |  25 +-
 arch/x86/kvm/Kconfig                          |  11 +
 arch/x86/kvm/Makefile                         |   1 +
 arch/x86/kvm/emulate.c                        | 355 +----------
 arch/x86/kvm/kvm_cache_regs.h                 |   5 -
 arch/x86/kvm/kvm_emulate.h                    |  47 +-
 arch/x86/kvm/lapic.c                          |   8 +-
 arch/x86/kvm/lapic.h                          |   2 +-
 arch/x86/kvm/mmu/mmu.c                        |   1 +
 arch/x86/kvm/smm.c                            | 576 ++++++++++++++++++
 arch/x86/kvm/smm.h                            |  37 ++
 arch/x86/kvm/svm/nested.c                     |   3 +
 arch/x86/kvm/svm/svm.c                        |  11 +-
 arch/x86/kvm/vmx/nested.c                     |   1 +
 arch/x86/kvm/vmx/vmx.c                        |   7 +
 arch/x86/kvm/x86.c                            | 371 ++---------
 tools/testing/selftests/kvm/x86_64/smm_test.c |   2 +
 18 files changed, 741 insertions(+), 724 deletions(-)
 create mode 100644 arch/x86/kvm/smm.c
 create mode 100644 arch/x86/kvm/smm.h

-- 
2.31.1


^ permalink raw reply	[flat|nested] 12+ messages in thread

* [PATCH 01/10] KVM: x86: start moving SMM-related functions to new files
  2022-10-27 16:49 [PATCH v3 0/10] KVM: x86: allow compiling out SMM support Paolo Bonzini
@ 2022-10-27 16:49 ` Paolo Bonzini
  2022-10-27 16:49 ` [PATCH 02/10] KVM: x86: move SMM entry to a new file Paolo Bonzini
                   ` (8 subsequent siblings)
  9 siblings, 0 replies; 12+ messages in thread
From: Paolo Bonzini @ 2022-10-27 16:49 UTC (permalink / raw)
  To: linux-kernel, kvm; +Cc: mlevitsk, seanjc

Create a new header and source with code related to system management
mode emulation.  Entry and exit will move there too; for now,
opportunistically rename put_smstate to PUT_SMSTATE while moving
it to smm.h, and adjust the SMM state saving code.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220929172016.319443-2-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/include/asm/kvm_host.h |   6 --
 arch/x86/kvm/Makefile           |   1 +
 arch/x86/kvm/emulate.c          |   1 +
 arch/x86/kvm/kvm_cache_regs.h   |   5 --
 arch/x86/kvm/lapic.c            |   8 +-
 arch/x86/kvm/lapic.h            |   2 +-
 arch/x86/kvm/mmu/mmu.c          |   1 +
 arch/x86/kvm/smm.c              |  37 ++++++++
 arch/x86/kvm/smm.h              |  25 ++++++
 arch/x86/kvm/svm/nested.c       |   1 +
 arch/x86/kvm/svm/svm.c          |   5 +-
 arch/x86/kvm/vmx/nested.c       |   1 +
 arch/x86/kvm/vmx/vmx.c          |   1 +
 arch/x86/kvm/x86.c              | 148 ++++++++++++--------------------
 14 files changed, 132 insertions(+), 110 deletions(-)
 create mode 100644 arch/x86/kvm/smm.c
 create mode 100644 arch/x86/kvm/smm.h

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index ff7dfb488680..d489548bf247 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -2082,12 +2082,6 @@ static inline int kvm_cpu_get_apicid(int mps_cpu)
 #endif
 }
 
-#define put_smstate(type, buf, offset, val)                      \
-	*(type *)((buf) + (offset) - 0x7e00) = val
-
-#define GET_SMSTATE(type, buf, offset)		\
-	(*(type *)((buf) + (offset) - 0x7e00))
-
 int kvm_cpu_dirty_log_size(void);
 
 int memslot_rmap_alloc(struct kvm_memory_slot *slot, unsigned long npages);
diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index 30f244b64523..ec6f7656254b 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -20,6 +20,7 @@ endif
 
 kvm-$(CONFIG_X86_64) += mmu/tdp_iter.o mmu/tdp_mmu.o
 kvm-$(CONFIG_KVM_XEN)	+= xen.o
+kvm-y			+= smm.o
 
 kvm-intel-y		+= vmx/vmx.o vmx/vmenter.o vmx/pmu_intel.o vmx/vmcs12.o \
 			   vmx/evmcs.o vmx/nested.o vmx/posted_intr.o
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index 3b27622d4642..de09660a61e5 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -30,6 +30,7 @@
 #include "tss.h"
 #include "mmu.h"
 #include "pmu.h"
+#include "smm.h"
 
 /*
  * Operand types
diff --git a/arch/x86/kvm/kvm_cache_regs.h b/arch/x86/kvm/kvm_cache_regs.h
index 3febc342360c..c09174f73a34 100644
--- a/arch/x86/kvm/kvm_cache_regs.h
+++ b/arch/x86/kvm/kvm_cache_regs.h
@@ -200,9 +200,4 @@ static inline bool is_guest_mode(struct kvm_vcpu *vcpu)
 	return vcpu->arch.hflags & HF_GUEST_MASK;
 }
 
-static inline bool is_smm(struct kvm_vcpu *vcpu)
-{
-	return vcpu->arch.hflags & HF_SMM_MASK;
-}
-
 #endif
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index d7639d126e6c..1bb63746e991 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -42,6 +42,7 @@
 #include "x86.h"
 #include "cpuid.h"
 #include "hyperv.h"
+#include "smm.h"
 
 #ifndef CONFIG_X86_64
 #define mod_64(x, y) ((x) - (y) * div64_u64(x, y))
@@ -1170,9 +1171,10 @@ static int __apic_accept_irq(struct kvm_lapic *apic, int delivery_mode,
 		break;
 
 	case APIC_DM_SMI:
-		result = 1;
-		kvm_make_request(KVM_REQ_SMI, vcpu);
-		kvm_vcpu_kick(vcpu);
+		if (!kvm_inject_smi(vcpu)) {
+			kvm_vcpu_kick(vcpu);
+			result = 1;
+		}
 		break;
 
 	case APIC_DM_NMI:
diff --git a/arch/x86/kvm/lapic.h b/arch/x86/kvm/lapic.h
index a5ac4a5a5179..28e3769066e2 100644
--- a/arch/x86/kvm/lapic.h
+++ b/arch/x86/kvm/lapic.h
@@ -7,7 +7,7 @@
 #include <linux/kvm_host.h>
 
 #include "hyperv.h"
-#include "kvm_cache_regs.h"
+#include "smm.h"
 
 #define KVM_APIC_INIT		0
 #define KVM_APIC_SIPI		1
diff --git a/arch/x86/kvm/mmu/mmu.c b/arch/x86/kvm/mmu/mmu.c
index 2640871bdcf1..f8c92a4a35fa 100644
--- a/arch/x86/kvm/mmu/mmu.c
+++ b/arch/x86/kvm/mmu/mmu.c
@@ -22,6 +22,7 @@
 #include "tdp_mmu.h"
 #include "x86.h"
 #include "kvm_cache_regs.h"
+#include "smm.h"
 #include "kvm_emulate.h"
 #include "cpuid.h"
 #include "spte.h"
diff --git a/arch/x86/kvm/smm.c b/arch/x86/kvm/smm.c
new file mode 100644
index 000000000000..b91c48d91f6e
--- /dev/null
+++ b/arch/x86/kvm/smm.c
@@ -0,0 +1,37 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#include <linux/kvm_host.h>
+#include "x86.h"
+#include "kvm_cache_regs.h"
+#include "kvm_emulate.h"
+#include "smm.h"
+#include "trace.h"
+
+void kvm_smm_changed(struct kvm_vcpu *vcpu, bool entering_smm)
+{
+	trace_kvm_smm_transition(vcpu->vcpu_id, vcpu->arch.smbase, entering_smm);
+
+	if (entering_smm) {
+		vcpu->arch.hflags |= HF_SMM_MASK;
+	} else {
+		vcpu->arch.hflags &= ~(HF_SMM_MASK | HF_SMM_INSIDE_NMI_MASK);
+
+		/* Process a latched INIT or SMI, if any.  */
+		kvm_make_request(KVM_REQ_EVENT, vcpu);
+
+		/*
+		 * Even if KVM_SET_SREGS2 loaded PDPTRs out of band,
+		 * on SMM exit we still need to reload them from
+		 * guest memory
+		 */
+		vcpu->arch.pdptrs_from_userspace = false;
+	}
+
+	kvm_mmu_reset_context(vcpu);
+}
+
+void process_smi(struct kvm_vcpu *vcpu)
+{
+	vcpu->arch.smi_pending = true;
+	kvm_make_request(KVM_REQ_EVENT, vcpu);
+}
diff --git a/arch/x86/kvm/smm.h b/arch/x86/kvm/smm.h
new file mode 100644
index 000000000000..d85d4ccd32dd
--- /dev/null
+++ b/arch/x86/kvm/smm.h
@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef ASM_KVM_SMM_H
+#define ASM_KVM_SMM_H
+
+#define GET_SMSTATE(type, buf, offset)		\
+	(*(type *)((buf) + (offset) - 0x7e00))
+
+#define PUT_SMSTATE(type, buf, offset, val)                      \
+	*(type *)((buf) + (offset) - 0x7e00) = val
+
+static inline int kvm_inject_smi(struct kvm_vcpu *vcpu)
+{
+	kvm_make_request(KVM_REQ_SMI, vcpu);
+	return 0;
+}
+
+static inline bool is_smm(struct kvm_vcpu *vcpu)
+{
+	return vcpu->arch.hflags & HF_SMM_MASK;
+}
+
+void kvm_smm_changed(struct kvm_vcpu *vcpu, bool in_smm);
+void process_smi(struct kvm_vcpu *vcpu);
+
+#endif
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index 4c620999d230..cc0fd75f7cba 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -25,6 +25,7 @@
 #include "trace.h"
 #include "mmu.h"
 #include "x86.h"
+#include "smm.h"
 #include "cpuid.h"
 #include "lapic.h"
 #include "svm.h"
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 58f0077d9357..496ee7d1ae2f 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -6,6 +6,7 @@
 #include "mmu.h"
 #include "kvm_cache_regs.h"
 #include "x86.h"
+#include "smm.h"
 #include "cpuid.h"
 #include "pmu.h"
 
@@ -4442,9 +4443,9 @@ static int svm_enter_smm(struct kvm_vcpu *vcpu, char *smstate)
 		return 0;
 
 	/* FED8h - SVM Guest */
-	put_smstate(u64, smstate, 0x7ed8, 1);
+	PUT_SMSTATE(u64, smstate, 0x7ed8, 1);
 	/* FEE0h - SVM Guest VMCB Physical Address */
-	put_smstate(u64, smstate, 0x7ee0, svm->nested.vmcb12_gpa);
+	PUT_SMSTATE(u64, smstate, 0x7ee0, svm->nested.vmcb12_gpa);
 
 	svm->vmcb->save.rax = vcpu->arch.regs[VCPU_REGS_RAX];
 	svm->vmcb->save.rsp = vcpu->arch.regs[VCPU_REGS_RSP];
diff --git a/arch/x86/kvm/vmx/nested.c b/arch/x86/kvm/vmx/nested.c
index 0c62352dda6a..61a2e551640a 100644
--- a/arch/x86/kvm/vmx/nested.c
+++ b/arch/x86/kvm/vmx/nested.c
@@ -16,6 +16,7 @@
 #include "trace.h"
 #include "vmx.h"
 #include "x86.h"
+#include "smm.h"
 
 static bool __read_mostly enable_shadow_vmcs = 1;
 module_param_named(enable_shadow_vmcs, enable_shadow_vmcs, bool, S_IRUGO);
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 65f092e4a81b..b459ddf30abd 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -66,6 +66,7 @@
 #include "vmcs12.h"
 #include "vmx.h"
 #include "x86.h"
+#include "smm.h"
 
 MODULE_AUTHOR("Qumranet");
 MODULE_LICENSE("GPL");
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 9cccc2150283..54909cd4863f 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -30,6 +30,7 @@
 #include "hyperv.h"
 #include "lapic.h"
 #include "xen.h"
+#include "smm.h"
 
 #include <linux/clocksource.h>
 #include <linux/interrupt.h>
@@ -119,7 +120,6 @@ static u64 __read_mostly cr4_reserved_bits = CR4_RESERVED_BITS;
 
 static void update_cr8_intercept(struct kvm_vcpu *vcpu);
 static void process_nmi(struct kvm_vcpu *vcpu);
-static void process_smi(struct kvm_vcpu *vcpu);
 static void enter_smm(struct kvm_vcpu *vcpu);
 static void __kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags);
 static void store_regs(struct kvm_vcpu *vcpu);
@@ -4888,13 +4888,6 @@ static int kvm_vcpu_ioctl_nmi(struct kvm_vcpu *vcpu)
 	return 0;
 }
 
-static int kvm_vcpu_ioctl_smi(struct kvm_vcpu *vcpu)
-{
-	kvm_make_request(KVM_REQ_SMI, vcpu);
-
-	return 0;
-}
-
 static int vcpu_ioctl_tpr_access_reporting(struct kvm_vcpu *vcpu,
 					   struct kvm_tpr_access_ctl *tac)
 {
@@ -5117,8 +5110,6 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu,
 	memset(&events->reserved, 0, sizeof(events->reserved));
 }
 
-static void kvm_smm_changed(struct kvm_vcpu *vcpu, bool entering_smm);
-
 static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
 					      struct kvm_vcpu_events *events)
 {
@@ -5571,7 +5562,7 @@ long kvm_arch_vcpu_ioctl(struct file *filp,
 		break;
 	}
 	case KVM_SMI: {
-		r = kvm_vcpu_ioctl_smi(vcpu);
+		r = kvm_inject_smi(vcpu);
 		break;
 	}
 	case KVM_SET_CPUID: {
@@ -8568,29 +8559,6 @@ static bool retry_instruction(struct x86_emulate_ctxt *ctxt,
 static int complete_emulated_mmio(struct kvm_vcpu *vcpu);
 static int complete_emulated_pio(struct kvm_vcpu *vcpu);
 
-static void kvm_smm_changed(struct kvm_vcpu *vcpu, bool entering_smm)
-{
-	trace_kvm_smm_transition(vcpu->vcpu_id, vcpu->arch.smbase, entering_smm);
-
-	if (entering_smm) {
-		vcpu->arch.hflags |= HF_SMM_MASK;
-	} else {
-		vcpu->arch.hflags &= ~(HF_SMM_MASK | HF_SMM_INSIDE_NMI_MASK);
-
-		/* Process a latched INIT or SMI, if any.  */
-		kvm_make_request(KVM_REQ_EVENT, vcpu);
-
-		/*
-		 * Even if KVM_SET_SREGS2 loaded PDPTRs out of band,
-		 * on SMM exit we still need to reload them from
-		 * guest memory
-		 */
-		vcpu->arch.pdptrs_from_userspace = false;
-	}
-
-	kvm_mmu_reset_context(vcpu);
-}
-
 static int kvm_vcpu_check_hw_bp(unsigned long addr, u32 type, u32 dr7,
 				unsigned long *db)
 {
@@ -10087,16 +10055,16 @@ static void enter_smm_save_seg_32(struct kvm_vcpu *vcpu, char *buf, int n)
 	int offset;
 
 	kvm_get_segment(vcpu, &seg, n);
-	put_smstate(u32, buf, 0x7fa8 + n * 4, seg.selector);
+	PUT_SMSTATE(u32, buf, 0x7fa8 + n * 4, seg.selector);
 
 	if (n < 3)
 		offset = 0x7f84 + n * 12;
 	else
 		offset = 0x7f2c + (n - 3) * 12;
 
-	put_smstate(u32, buf, offset + 8, seg.base);
-	put_smstate(u32, buf, offset + 4, seg.limit);
-	put_smstate(u32, buf, offset, enter_smm_get_segment_flags(&seg));
+	PUT_SMSTATE(u32, buf, offset + 8, seg.base);
+	PUT_SMSTATE(u32, buf, offset + 4, seg.limit);
+	PUT_SMSTATE(u32, buf, offset, enter_smm_get_segment_flags(&seg));
 }
 
 #ifdef CONFIG_X86_64
@@ -10110,10 +10078,10 @@ static void enter_smm_save_seg_64(struct kvm_vcpu *vcpu, char *buf, int n)
 	offset = 0x7e00 + n * 16;
 
 	flags = enter_smm_get_segment_flags(&seg) >> 8;
-	put_smstate(u16, buf, offset, seg.selector);
-	put_smstate(u16, buf, offset + 2, flags);
-	put_smstate(u32, buf, offset + 4, seg.limit);
-	put_smstate(u64, buf, offset + 8, seg.base);
+	PUT_SMSTATE(u16, buf, offset, seg.selector);
+	PUT_SMSTATE(u16, buf, offset + 2, flags);
+	PUT_SMSTATE(u32, buf, offset + 4, seg.limit);
+	PUT_SMSTATE(u64, buf, offset + 8, seg.base);
 }
 #endif
 
@@ -10124,47 +10092,47 @@ static void enter_smm_save_state_32(struct kvm_vcpu *vcpu, char *buf)
 	unsigned long val;
 	int i;
 
-	put_smstate(u32, buf, 0x7ffc, kvm_read_cr0(vcpu));
-	put_smstate(u32, buf, 0x7ff8, kvm_read_cr3(vcpu));
-	put_smstate(u32, buf, 0x7ff4, kvm_get_rflags(vcpu));
-	put_smstate(u32, buf, 0x7ff0, kvm_rip_read(vcpu));
+	PUT_SMSTATE(u32, buf, 0x7ffc, kvm_read_cr0(vcpu));
+	PUT_SMSTATE(u32, buf, 0x7ff8, kvm_read_cr3(vcpu));
+	PUT_SMSTATE(u32, buf, 0x7ff4, kvm_get_rflags(vcpu));
+	PUT_SMSTATE(u32, buf, 0x7ff0, kvm_rip_read(vcpu));
 
 	for (i = 0; i < 8; i++)
-		put_smstate(u32, buf, 0x7fd0 + i * 4, kvm_register_read_raw(vcpu, i));
+		PUT_SMSTATE(u32, buf, 0x7fd0 + i * 4, kvm_register_read_raw(vcpu, i));
 
 	kvm_get_dr(vcpu, 6, &val);
-	put_smstate(u32, buf, 0x7fcc, (u32)val);
+	PUT_SMSTATE(u32, buf, 0x7fcc, (u32)val);
 	kvm_get_dr(vcpu, 7, &val);
-	put_smstate(u32, buf, 0x7fc8, (u32)val);
+	PUT_SMSTATE(u32, buf, 0x7fc8, (u32)val);
 
 	kvm_get_segment(vcpu, &seg, VCPU_SREG_TR);
-	put_smstate(u32, buf, 0x7fc4, seg.selector);
-	put_smstate(u32, buf, 0x7f64, seg.base);
-	put_smstate(u32, buf, 0x7f60, seg.limit);
-	put_smstate(u32, buf, 0x7f5c, enter_smm_get_segment_flags(&seg));
+	PUT_SMSTATE(u32, buf, 0x7fc4, seg.selector);
+	PUT_SMSTATE(u32, buf, 0x7f64, seg.base);
+	PUT_SMSTATE(u32, buf, 0x7f60, seg.limit);
+	PUT_SMSTATE(u32, buf, 0x7f5c, enter_smm_get_segment_flags(&seg));
 
 	kvm_get_segment(vcpu, &seg, VCPU_SREG_LDTR);
-	put_smstate(u32, buf, 0x7fc0, seg.selector);
-	put_smstate(u32, buf, 0x7f80, seg.base);
-	put_smstate(u32, buf, 0x7f7c, seg.limit);
-	put_smstate(u32, buf, 0x7f78, enter_smm_get_segment_flags(&seg));
+	PUT_SMSTATE(u32, buf, 0x7fc0, seg.selector);
+	PUT_SMSTATE(u32, buf, 0x7f80, seg.base);
+	PUT_SMSTATE(u32, buf, 0x7f7c, seg.limit);
+	PUT_SMSTATE(u32, buf, 0x7f78, enter_smm_get_segment_flags(&seg));
 
 	static_call(kvm_x86_get_gdt)(vcpu, &dt);
-	put_smstate(u32, buf, 0x7f74, dt.address);
-	put_smstate(u32, buf, 0x7f70, dt.size);
+	PUT_SMSTATE(u32, buf, 0x7f74, dt.address);
+	PUT_SMSTATE(u32, buf, 0x7f70, dt.size);
 
 	static_call(kvm_x86_get_idt)(vcpu, &dt);
-	put_smstate(u32, buf, 0x7f58, dt.address);
-	put_smstate(u32, buf, 0x7f54, dt.size);
+	PUT_SMSTATE(u32, buf, 0x7f58, dt.address);
+	PUT_SMSTATE(u32, buf, 0x7f54, dt.size);
 
 	for (i = 0; i < 6; i++)
 		enter_smm_save_seg_32(vcpu, buf, i);
 
-	put_smstate(u32, buf, 0x7f14, kvm_read_cr4(vcpu));
+	PUT_SMSTATE(u32, buf, 0x7f14, kvm_read_cr4(vcpu));
 
 	/* revision id */
-	put_smstate(u32, buf, 0x7efc, 0x00020000);
-	put_smstate(u32, buf, 0x7ef8, vcpu->arch.smbase);
+	PUT_SMSTATE(u32, buf, 0x7efc, 0x00020000);
+	PUT_SMSTATE(u32, buf, 0x7ef8, vcpu->arch.smbase);
 }
 
 #ifdef CONFIG_X86_64
@@ -10176,46 +10144,46 @@ static void enter_smm_save_state_64(struct kvm_vcpu *vcpu, char *buf)
 	int i;
 
 	for (i = 0; i < 16; i++)
-		put_smstate(u64, buf, 0x7ff8 - i * 8, kvm_register_read_raw(vcpu, i));
+		PUT_SMSTATE(u64, buf, 0x7ff8 - i * 8, kvm_register_read_raw(vcpu, i));
 
-	put_smstate(u64, buf, 0x7f78, kvm_rip_read(vcpu));
-	put_smstate(u32, buf, 0x7f70, kvm_get_rflags(vcpu));
+	PUT_SMSTATE(u64, buf, 0x7f78, kvm_rip_read(vcpu));
+	PUT_SMSTATE(u32, buf, 0x7f70, kvm_get_rflags(vcpu));
 
 	kvm_get_dr(vcpu, 6, &val);
-	put_smstate(u64, buf, 0x7f68, val);
+	PUT_SMSTATE(u64, buf, 0x7f68, val);
 	kvm_get_dr(vcpu, 7, &val);
-	put_smstate(u64, buf, 0x7f60, val);
+	PUT_SMSTATE(u64, buf, 0x7f60, val);
 
-	put_smstate(u64, buf, 0x7f58, kvm_read_cr0(vcpu));
-	put_smstate(u64, buf, 0x7f50, kvm_read_cr3(vcpu));
-	put_smstate(u64, buf, 0x7f48, kvm_read_cr4(vcpu));
+	PUT_SMSTATE(u64, buf, 0x7f58, kvm_read_cr0(vcpu));
+	PUT_SMSTATE(u64, buf, 0x7f50, kvm_read_cr3(vcpu));
+	PUT_SMSTATE(u64, buf, 0x7f48, kvm_read_cr4(vcpu));
 
-	put_smstate(u32, buf, 0x7f00, vcpu->arch.smbase);
+	PUT_SMSTATE(u32, buf, 0x7f00, vcpu->arch.smbase);
 
 	/* revision id */
-	put_smstate(u32, buf, 0x7efc, 0x00020064);
+	PUT_SMSTATE(u32, buf, 0x7efc, 0x00020064);
 
-	put_smstate(u64, buf, 0x7ed0, vcpu->arch.efer);
+	PUT_SMSTATE(u64, buf, 0x7ed0, vcpu->arch.efer);
 
 	kvm_get_segment(vcpu, &seg, VCPU_SREG_TR);
-	put_smstate(u16, buf, 0x7e90, seg.selector);
-	put_smstate(u16, buf, 0x7e92, enter_smm_get_segment_flags(&seg) >> 8);
-	put_smstate(u32, buf, 0x7e94, seg.limit);
-	put_smstate(u64, buf, 0x7e98, seg.base);
+	PUT_SMSTATE(u16, buf, 0x7e90, seg.selector);
+	PUT_SMSTATE(u16, buf, 0x7e92, enter_smm_get_segment_flags(&seg) >> 8);
+	PUT_SMSTATE(u32, buf, 0x7e94, seg.limit);
+	PUT_SMSTATE(u64, buf, 0x7e98, seg.base);
 
 	static_call(kvm_x86_get_idt)(vcpu, &dt);
-	put_smstate(u32, buf, 0x7e84, dt.size);
-	put_smstate(u64, buf, 0x7e88, dt.address);
+	PUT_SMSTATE(u32, buf, 0x7e84, dt.size);
+	PUT_SMSTATE(u64, buf, 0x7e88, dt.address);
 
 	kvm_get_segment(vcpu, &seg, VCPU_SREG_LDTR);
-	put_smstate(u16, buf, 0x7e70, seg.selector);
-	put_smstate(u16, buf, 0x7e72, enter_smm_get_segment_flags(&seg) >> 8);
-	put_smstate(u32, buf, 0x7e74, seg.limit);
-	put_smstate(u64, buf, 0x7e78, seg.base);
+	PUT_SMSTATE(u16, buf, 0x7e70, seg.selector);
+	PUT_SMSTATE(u16, buf, 0x7e72, enter_smm_get_segment_flags(&seg) >> 8);
+	PUT_SMSTATE(u32, buf, 0x7e74, seg.limit);
+	PUT_SMSTATE(u64, buf, 0x7e78, seg.base);
 
 	static_call(kvm_x86_get_gdt)(vcpu, &dt);
-	put_smstate(u32, buf, 0x7e64, dt.size);
-	put_smstate(u64, buf, 0x7e68, dt.address);
+	PUT_SMSTATE(u32, buf, 0x7e64, dt.size);
+	PUT_SMSTATE(u64, buf, 0x7e68, dt.address);
 
 	for (i = 0; i < 6; i++)
 		enter_smm_save_seg_64(vcpu, buf, i);
@@ -10301,12 +10269,6 @@ static void enter_smm(struct kvm_vcpu *vcpu)
 	kvm_mmu_reset_context(vcpu);
 }
 
-static void process_smi(struct kvm_vcpu *vcpu)
-{
-	vcpu->arch.smi_pending = true;
-	kvm_make_request(KVM_REQ_EVENT, vcpu);
-}
-
 void kvm_make_scan_ioapic_request_mask(struct kvm *kvm,
 				       unsigned long *vcpu_bitmap)
 {
-- 
2.31.1



^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH 02/10] KVM: x86: move SMM entry to a new file
  2022-10-27 16:49 [PATCH v3 0/10] KVM: x86: allow compiling out SMM support Paolo Bonzini
  2022-10-27 16:49 ` [PATCH 01/10] KVM: x86: start moving SMM-related functions to new files Paolo Bonzini
@ 2022-10-27 16:49 ` Paolo Bonzini
  2022-10-27 16:49 ` [PATCH 03/10] KVM: x86: move SMM exit " Paolo Bonzini
                   ` (7 subsequent siblings)
  9 siblings, 0 replies; 12+ messages in thread
From: Paolo Bonzini @ 2022-10-27 16:49 UTC (permalink / raw)
  To: linux-kernel, kvm; +Cc: mlevitsk, seanjc

Some users of KVM implement the UEFI variable store through a paravirtual
device that does not require the "SMM lockbox" component of edk2, and
would like to compile out system management mode.  In preparation for
that, move the SMM entry code out of x86.c and into a new file.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220929172016.319443-3-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/include/asm/kvm_host.h |   1 +
 arch/x86/kvm/smm.c              | 235 +++++++++++++++++++++++++++++++
 arch/x86/kvm/smm.h              |   1 +
 arch/x86/kvm/x86.c              | 239 +-------------------------------
 4 files changed, 239 insertions(+), 237 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index d489548bf247..38451bf71b80 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1839,6 +1839,7 @@ int kvm_emulate_ap_reset_hold(struct kvm_vcpu *vcpu);
 int kvm_emulate_wbinvd(struct kvm_vcpu *vcpu);
 
 void kvm_get_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg);
+void kvm_set_segment(struct kvm_vcpu *vcpu, struct kvm_segment *var, int seg);
 int kvm_load_segment_descriptor(struct kvm_vcpu *vcpu, u16 selector, int seg);
 void kvm_vcpu_deliver_sipi_vector(struct kvm_vcpu *vcpu, u8 vector);
 
diff --git a/arch/x86/kvm/smm.c b/arch/x86/kvm/smm.c
index b91c48d91f6e..26a6859e421f 100644
--- a/arch/x86/kvm/smm.c
+++ b/arch/x86/kvm/smm.c
@@ -5,6 +5,7 @@
 #include "kvm_cache_regs.h"
 #include "kvm_emulate.h"
 #include "smm.h"
+#include "cpuid.h"
 #include "trace.h"
 
 void kvm_smm_changed(struct kvm_vcpu *vcpu, bool entering_smm)
@@ -35,3 +36,237 @@ void process_smi(struct kvm_vcpu *vcpu)
 	vcpu->arch.smi_pending = true;
 	kvm_make_request(KVM_REQ_EVENT, vcpu);
 }
+
+static u32 enter_smm_get_segment_flags(struct kvm_segment *seg)
+{
+	u32 flags = 0;
+	flags |= seg->g       << 23;
+	flags |= seg->db      << 22;
+	flags |= seg->l       << 21;
+	flags |= seg->avl     << 20;
+	flags |= seg->present << 15;
+	flags |= seg->dpl     << 13;
+	flags |= seg->s       << 12;
+	flags |= seg->type    << 8;
+	return flags;
+}
+
+static void enter_smm_save_seg_32(struct kvm_vcpu *vcpu, char *buf, int n)
+{
+	struct kvm_segment seg;
+	int offset;
+
+	kvm_get_segment(vcpu, &seg, n);
+	PUT_SMSTATE(u32, buf, 0x7fa8 + n * 4, seg.selector);
+
+	if (n < 3)
+		offset = 0x7f84 + n * 12;
+	else
+		offset = 0x7f2c + (n - 3) * 12;
+
+	PUT_SMSTATE(u32, buf, offset + 8, seg.base);
+	PUT_SMSTATE(u32, buf, offset + 4, seg.limit);
+	PUT_SMSTATE(u32, buf, offset, enter_smm_get_segment_flags(&seg));
+}
+
+#ifdef CONFIG_X86_64
+static void enter_smm_save_seg_64(struct kvm_vcpu *vcpu, char *buf, int n)
+{
+	struct kvm_segment seg;
+	int offset;
+	u16 flags;
+
+	kvm_get_segment(vcpu, &seg, n);
+	offset = 0x7e00 + n * 16;
+
+	flags = enter_smm_get_segment_flags(&seg) >> 8;
+	PUT_SMSTATE(u16, buf, offset, seg.selector);
+	PUT_SMSTATE(u16, buf, offset + 2, flags);
+	PUT_SMSTATE(u32, buf, offset + 4, seg.limit);
+	PUT_SMSTATE(u64, buf, offset + 8, seg.base);
+}
+#endif
+
+static void enter_smm_save_state_32(struct kvm_vcpu *vcpu, char *buf)
+{
+	struct desc_ptr dt;
+	struct kvm_segment seg;
+	unsigned long val;
+	int i;
+
+	PUT_SMSTATE(u32, buf, 0x7ffc, kvm_read_cr0(vcpu));
+	PUT_SMSTATE(u32, buf, 0x7ff8, kvm_read_cr3(vcpu));
+	PUT_SMSTATE(u32, buf, 0x7ff4, kvm_get_rflags(vcpu));
+	PUT_SMSTATE(u32, buf, 0x7ff0, kvm_rip_read(vcpu));
+
+	for (i = 0; i < 8; i++)
+		PUT_SMSTATE(u32, buf, 0x7fd0 + i * 4, kvm_register_read_raw(vcpu, i));
+
+	kvm_get_dr(vcpu, 6, &val);
+	PUT_SMSTATE(u32, buf, 0x7fcc, (u32)val);
+	kvm_get_dr(vcpu, 7, &val);
+	PUT_SMSTATE(u32, buf, 0x7fc8, (u32)val);
+
+	kvm_get_segment(vcpu, &seg, VCPU_SREG_TR);
+	PUT_SMSTATE(u32, buf, 0x7fc4, seg.selector);
+	PUT_SMSTATE(u32, buf, 0x7f64, seg.base);
+	PUT_SMSTATE(u32, buf, 0x7f60, seg.limit);
+	PUT_SMSTATE(u32, buf, 0x7f5c, enter_smm_get_segment_flags(&seg));
+
+	kvm_get_segment(vcpu, &seg, VCPU_SREG_LDTR);
+	PUT_SMSTATE(u32, buf, 0x7fc0, seg.selector);
+	PUT_SMSTATE(u32, buf, 0x7f80, seg.base);
+	PUT_SMSTATE(u32, buf, 0x7f7c, seg.limit);
+	PUT_SMSTATE(u32, buf, 0x7f78, enter_smm_get_segment_flags(&seg));
+
+	static_call(kvm_x86_get_gdt)(vcpu, &dt);
+	PUT_SMSTATE(u32, buf, 0x7f74, dt.address);
+	PUT_SMSTATE(u32, buf, 0x7f70, dt.size);
+
+	static_call(kvm_x86_get_idt)(vcpu, &dt);
+	PUT_SMSTATE(u32, buf, 0x7f58, dt.address);
+	PUT_SMSTATE(u32, buf, 0x7f54, dt.size);
+
+	for (i = 0; i < 6; i++)
+		enter_smm_save_seg_32(vcpu, buf, i);
+
+	PUT_SMSTATE(u32, buf, 0x7f14, kvm_read_cr4(vcpu));
+
+	/* revision id */
+	PUT_SMSTATE(u32, buf, 0x7efc, 0x00020000);
+	PUT_SMSTATE(u32, buf, 0x7ef8, vcpu->arch.smbase);
+}
+
+#ifdef CONFIG_X86_64
+static void enter_smm_save_state_64(struct kvm_vcpu *vcpu, char *buf)
+{
+	struct desc_ptr dt;
+	struct kvm_segment seg;
+	unsigned long val;
+	int i;
+
+	for (i = 0; i < 16; i++)
+		PUT_SMSTATE(u64, buf, 0x7ff8 - i * 8, kvm_register_read_raw(vcpu, i));
+
+	PUT_SMSTATE(u64, buf, 0x7f78, kvm_rip_read(vcpu));
+	PUT_SMSTATE(u32, buf, 0x7f70, kvm_get_rflags(vcpu));
+
+	kvm_get_dr(vcpu, 6, &val);
+	PUT_SMSTATE(u64, buf, 0x7f68, val);
+	kvm_get_dr(vcpu, 7, &val);
+	PUT_SMSTATE(u64, buf, 0x7f60, val);
+
+	PUT_SMSTATE(u64, buf, 0x7f58, kvm_read_cr0(vcpu));
+	PUT_SMSTATE(u64, buf, 0x7f50, kvm_read_cr3(vcpu));
+	PUT_SMSTATE(u64, buf, 0x7f48, kvm_read_cr4(vcpu));
+
+	PUT_SMSTATE(u32, buf, 0x7f00, vcpu->arch.smbase);
+
+	/* revision id */
+	PUT_SMSTATE(u32, buf, 0x7efc, 0x00020064);
+
+	PUT_SMSTATE(u64, buf, 0x7ed0, vcpu->arch.efer);
+
+	kvm_get_segment(vcpu, &seg, VCPU_SREG_TR);
+	PUT_SMSTATE(u16, buf, 0x7e90, seg.selector);
+	PUT_SMSTATE(u16, buf, 0x7e92, enter_smm_get_segment_flags(&seg) >> 8);
+	PUT_SMSTATE(u32, buf, 0x7e94, seg.limit);
+	PUT_SMSTATE(u64, buf, 0x7e98, seg.base);
+
+	static_call(kvm_x86_get_idt)(vcpu, &dt);
+	PUT_SMSTATE(u32, buf, 0x7e84, dt.size);
+	PUT_SMSTATE(u64, buf, 0x7e88, dt.address);
+
+	kvm_get_segment(vcpu, &seg, VCPU_SREG_LDTR);
+	PUT_SMSTATE(u16, buf, 0x7e70, seg.selector);
+	PUT_SMSTATE(u16, buf, 0x7e72, enter_smm_get_segment_flags(&seg) >> 8);
+	PUT_SMSTATE(u32, buf, 0x7e74, seg.limit);
+	PUT_SMSTATE(u64, buf, 0x7e78, seg.base);
+
+	static_call(kvm_x86_get_gdt)(vcpu, &dt);
+	PUT_SMSTATE(u32, buf, 0x7e64, dt.size);
+	PUT_SMSTATE(u64, buf, 0x7e68, dt.address);
+
+	for (i = 0; i < 6; i++)
+		enter_smm_save_seg_64(vcpu, buf, i);
+}
+#endif
+
+void enter_smm(struct kvm_vcpu *vcpu)
+{
+	struct kvm_segment cs, ds;
+	struct desc_ptr dt;
+	unsigned long cr0;
+	char buf[512];
+
+	memset(buf, 0, 512);
+#ifdef CONFIG_X86_64
+	if (guest_cpuid_has(vcpu, X86_FEATURE_LM))
+		enter_smm_save_state_64(vcpu, buf);
+	else
+#endif
+		enter_smm_save_state_32(vcpu, buf);
+
+	/*
+	 * Give enter_smm() a chance to make ISA-specific changes to the vCPU
+	 * state (e.g. leave guest mode) after we've saved the state into the
+	 * SMM state-save area.
+	 */
+	static_call(kvm_x86_enter_smm)(vcpu, buf);
+
+	kvm_smm_changed(vcpu, true);
+	kvm_vcpu_write_guest(vcpu, vcpu->arch.smbase + 0xfe00, buf, sizeof(buf));
+
+	if (static_call(kvm_x86_get_nmi_mask)(vcpu))
+		vcpu->arch.hflags |= HF_SMM_INSIDE_NMI_MASK;
+	else
+		static_call(kvm_x86_set_nmi_mask)(vcpu, true);
+
+	kvm_set_rflags(vcpu, X86_EFLAGS_FIXED);
+	kvm_rip_write(vcpu, 0x8000);
+
+	cr0 = vcpu->arch.cr0 & ~(X86_CR0_PE | X86_CR0_EM | X86_CR0_TS | X86_CR0_PG);
+	static_call(kvm_x86_set_cr0)(vcpu, cr0);
+	vcpu->arch.cr0 = cr0;
+
+	static_call(kvm_x86_set_cr4)(vcpu, 0);
+
+	/* Undocumented: IDT limit is set to zero on entry to SMM.  */
+	dt.address = dt.size = 0;
+	static_call(kvm_x86_set_idt)(vcpu, &dt);
+
+	kvm_set_dr(vcpu, 7, DR7_FIXED_1);
+
+	cs.selector = (vcpu->arch.smbase >> 4) & 0xffff;
+	cs.base = vcpu->arch.smbase;
+
+	ds.selector = 0;
+	ds.base = 0;
+
+	cs.limit    = ds.limit = 0xffffffff;
+	cs.type     = ds.type = 0x3;
+	cs.dpl      = ds.dpl = 0;
+	cs.db       = ds.db = 0;
+	cs.s        = ds.s = 1;
+	cs.l        = ds.l = 0;
+	cs.g        = ds.g = 1;
+	cs.avl      = ds.avl = 0;
+	cs.present  = ds.present = 1;
+	cs.unusable = ds.unusable = 0;
+	cs.padding  = ds.padding = 0;
+
+	kvm_set_segment(vcpu, &cs, VCPU_SREG_CS);
+	kvm_set_segment(vcpu, &ds, VCPU_SREG_DS);
+	kvm_set_segment(vcpu, &ds, VCPU_SREG_ES);
+	kvm_set_segment(vcpu, &ds, VCPU_SREG_FS);
+	kvm_set_segment(vcpu, &ds, VCPU_SREG_GS);
+	kvm_set_segment(vcpu, &ds, VCPU_SREG_SS);
+
+#ifdef CONFIG_X86_64
+	if (guest_cpuid_has(vcpu, X86_FEATURE_LM))
+		static_call(kvm_x86_set_efer)(vcpu, 0);
+#endif
+
+	kvm_update_cpuid_runtime(vcpu);
+	kvm_mmu_reset_context(vcpu);
+}
diff --git a/arch/x86/kvm/smm.h b/arch/x86/kvm/smm.h
index d85d4ccd32dd..aacc6dac2c99 100644
--- a/arch/x86/kvm/smm.h
+++ b/arch/x86/kvm/smm.h
@@ -20,6 +20,7 @@ static inline bool is_smm(struct kvm_vcpu *vcpu)
 }
 
 void kvm_smm_changed(struct kvm_vcpu *vcpu, bool in_smm);
+void enter_smm(struct kvm_vcpu *vcpu);
 void process_smi(struct kvm_vcpu *vcpu);
 
 #endif
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 54909cd4863f..a03712d00883 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -120,7 +120,6 @@ static u64 __read_mostly cr4_reserved_bits = CR4_RESERVED_BITS;
 
 static void update_cr8_intercept(struct kvm_vcpu *vcpu);
 static void process_nmi(struct kvm_vcpu *vcpu);
-static void enter_smm(struct kvm_vcpu *vcpu);
 static void __kvm_set_rflags(struct kvm_vcpu *vcpu, unsigned long rflags);
 static void store_regs(struct kvm_vcpu *vcpu);
 static int sync_regs(struct kvm_vcpu *vcpu);
@@ -7107,8 +7106,8 @@ static int vcpu_mmio_read(struct kvm_vcpu *vcpu, gpa_t addr, int len, void *v)
 	return handled;
 }
 
-static void kvm_set_segment(struct kvm_vcpu *vcpu,
-			struct kvm_segment *var, int seg)
+void kvm_set_segment(struct kvm_vcpu *vcpu,
+		     struct kvm_segment *var, int seg)
 {
 	static_call(kvm_x86_set_segment)(vcpu, var, seg);
 }
@@ -10035,240 +10034,6 @@ static void process_nmi(struct kvm_vcpu *vcpu)
 	kvm_make_request(KVM_REQ_EVENT, vcpu);
 }
 
-static u32 enter_smm_get_segment_flags(struct kvm_segment *seg)
-{
-	u32 flags = 0;
-	flags |= seg->g       << 23;
-	flags |= seg->db      << 22;
-	flags |= seg->l       << 21;
-	flags |= seg->avl     << 20;
-	flags |= seg->present << 15;
-	flags |= seg->dpl     << 13;
-	flags |= seg->s       << 12;
-	flags |= seg->type    << 8;
-	return flags;
-}
-
-static void enter_smm_save_seg_32(struct kvm_vcpu *vcpu, char *buf, int n)
-{
-	struct kvm_segment seg;
-	int offset;
-
-	kvm_get_segment(vcpu, &seg, n);
-	PUT_SMSTATE(u32, buf, 0x7fa8 + n * 4, seg.selector);
-
-	if (n < 3)
-		offset = 0x7f84 + n * 12;
-	else
-		offset = 0x7f2c + (n - 3) * 12;
-
-	PUT_SMSTATE(u32, buf, offset + 8, seg.base);
-	PUT_SMSTATE(u32, buf, offset + 4, seg.limit);
-	PUT_SMSTATE(u32, buf, offset, enter_smm_get_segment_flags(&seg));
-}
-
-#ifdef CONFIG_X86_64
-static void enter_smm_save_seg_64(struct kvm_vcpu *vcpu, char *buf, int n)
-{
-	struct kvm_segment seg;
-	int offset;
-	u16 flags;
-
-	kvm_get_segment(vcpu, &seg, n);
-	offset = 0x7e00 + n * 16;
-
-	flags = enter_smm_get_segment_flags(&seg) >> 8;
-	PUT_SMSTATE(u16, buf, offset, seg.selector);
-	PUT_SMSTATE(u16, buf, offset + 2, flags);
-	PUT_SMSTATE(u32, buf, offset + 4, seg.limit);
-	PUT_SMSTATE(u64, buf, offset + 8, seg.base);
-}
-#endif
-
-static void enter_smm_save_state_32(struct kvm_vcpu *vcpu, char *buf)
-{
-	struct desc_ptr dt;
-	struct kvm_segment seg;
-	unsigned long val;
-	int i;
-
-	PUT_SMSTATE(u32, buf, 0x7ffc, kvm_read_cr0(vcpu));
-	PUT_SMSTATE(u32, buf, 0x7ff8, kvm_read_cr3(vcpu));
-	PUT_SMSTATE(u32, buf, 0x7ff4, kvm_get_rflags(vcpu));
-	PUT_SMSTATE(u32, buf, 0x7ff0, kvm_rip_read(vcpu));
-
-	for (i = 0; i < 8; i++)
-		PUT_SMSTATE(u32, buf, 0x7fd0 + i * 4, kvm_register_read_raw(vcpu, i));
-
-	kvm_get_dr(vcpu, 6, &val);
-	PUT_SMSTATE(u32, buf, 0x7fcc, (u32)val);
-	kvm_get_dr(vcpu, 7, &val);
-	PUT_SMSTATE(u32, buf, 0x7fc8, (u32)val);
-
-	kvm_get_segment(vcpu, &seg, VCPU_SREG_TR);
-	PUT_SMSTATE(u32, buf, 0x7fc4, seg.selector);
-	PUT_SMSTATE(u32, buf, 0x7f64, seg.base);
-	PUT_SMSTATE(u32, buf, 0x7f60, seg.limit);
-	PUT_SMSTATE(u32, buf, 0x7f5c, enter_smm_get_segment_flags(&seg));
-
-	kvm_get_segment(vcpu, &seg, VCPU_SREG_LDTR);
-	PUT_SMSTATE(u32, buf, 0x7fc0, seg.selector);
-	PUT_SMSTATE(u32, buf, 0x7f80, seg.base);
-	PUT_SMSTATE(u32, buf, 0x7f7c, seg.limit);
-	PUT_SMSTATE(u32, buf, 0x7f78, enter_smm_get_segment_flags(&seg));
-
-	static_call(kvm_x86_get_gdt)(vcpu, &dt);
-	PUT_SMSTATE(u32, buf, 0x7f74, dt.address);
-	PUT_SMSTATE(u32, buf, 0x7f70, dt.size);
-
-	static_call(kvm_x86_get_idt)(vcpu, &dt);
-	PUT_SMSTATE(u32, buf, 0x7f58, dt.address);
-	PUT_SMSTATE(u32, buf, 0x7f54, dt.size);
-
-	for (i = 0; i < 6; i++)
-		enter_smm_save_seg_32(vcpu, buf, i);
-
-	PUT_SMSTATE(u32, buf, 0x7f14, kvm_read_cr4(vcpu));
-
-	/* revision id */
-	PUT_SMSTATE(u32, buf, 0x7efc, 0x00020000);
-	PUT_SMSTATE(u32, buf, 0x7ef8, vcpu->arch.smbase);
-}
-
-#ifdef CONFIG_X86_64
-static void enter_smm_save_state_64(struct kvm_vcpu *vcpu, char *buf)
-{
-	struct desc_ptr dt;
-	struct kvm_segment seg;
-	unsigned long val;
-	int i;
-
-	for (i = 0; i < 16; i++)
-		PUT_SMSTATE(u64, buf, 0x7ff8 - i * 8, kvm_register_read_raw(vcpu, i));
-
-	PUT_SMSTATE(u64, buf, 0x7f78, kvm_rip_read(vcpu));
-	PUT_SMSTATE(u32, buf, 0x7f70, kvm_get_rflags(vcpu));
-
-	kvm_get_dr(vcpu, 6, &val);
-	PUT_SMSTATE(u64, buf, 0x7f68, val);
-	kvm_get_dr(vcpu, 7, &val);
-	PUT_SMSTATE(u64, buf, 0x7f60, val);
-
-	PUT_SMSTATE(u64, buf, 0x7f58, kvm_read_cr0(vcpu));
-	PUT_SMSTATE(u64, buf, 0x7f50, kvm_read_cr3(vcpu));
-	PUT_SMSTATE(u64, buf, 0x7f48, kvm_read_cr4(vcpu));
-
-	PUT_SMSTATE(u32, buf, 0x7f00, vcpu->arch.smbase);
-
-	/* revision id */
-	PUT_SMSTATE(u32, buf, 0x7efc, 0x00020064);
-
-	PUT_SMSTATE(u64, buf, 0x7ed0, vcpu->arch.efer);
-
-	kvm_get_segment(vcpu, &seg, VCPU_SREG_TR);
-	PUT_SMSTATE(u16, buf, 0x7e90, seg.selector);
-	PUT_SMSTATE(u16, buf, 0x7e92, enter_smm_get_segment_flags(&seg) >> 8);
-	PUT_SMSTATE(u32, buf, 0x7e94, seg.limit);
-	PUT_SMSTATE(u64, buf, 0x7e98, seg.base);
-
-	static_call(kvm_x86_get_idt)(vcpu, &dt);
-	PUT_SMSTATE(u32, buf, 0x7e84, dt.size);
-	PUT_SMSTATE(u64, buf, 0x7e88, dt.address);
-
-	kvm_get_segment(vcpu, &seg, VCPU_SREG_LDTR);
-	PUT_SMSTATE(u16, buf, 0x7e70, seg.selector);
-	PUT_SMSTATE(u16, buf, 0x7e72, enter_smm_get_segment_flags(&seg) >> 8);
-	PUT_SMSTATE(u32, buf, 0x7e74, seg.limit);
-	PUT_SMSTATE(u64, buf, 0x7e78, seg.base);
-
-	static_call(kvm_x86_get_gdt)(vcpu, &dt);
-	PUT_SMSTATE(u32, buf, 0x7e64, dt.size);
-	PUT_SMSTATE(u64, buf, 0x7e68, dt.address);
-
-	for (i = 0; i < 6; i++)
-		enter_smm_save_seg_64(vcpu, buf, i);
-}
-#endif
-
-static void enter_smm(struct kvm_vcpu *vcpu)
-{
-	struct kvm_segment cs, ds;
-	struct desc_ptr dt;
-	unsigned long cr0;
-	char buf[512];
-
-	memset(buf, 0, 512);
-#ifdef CONFIG_X86_64
-	if (guest_cpuid_has(vcpu, X86_FEATURE_LM))
-		enter_smm_save_state_64(vcpu, buf);
-	else
-#endif
-		enter_smm_save_state_32(vcpu, buf);
-
-	/*
-	 * Give enter_smm() a chance to make ISA-specific changes to the vCPU
-	 * state (e.g. leave guest mode) after we've saved the state into the
-	 * SMM state-save area.
-	 */
-	static_call(kvm_x86_enter_smm)(vcpu, buf);
-
-	kvm_smm_changed(vcpu, true);
-	kvm_vcpu_write_guest(vcpu, vcpu->arch.smbase + 0xfe00, buf, sizeof(buf));
-
-	if (static_call(kvm_x86_get_nmi_mask)(vcpu))
-		vcpu->arch.hflags |= HF_SMM_INSIDE_NMI_MASK;
-	else
-		static_call(kvm_x86_set_nmi_mask)(vcpu, true);
-
-	kvm_set_rflags(vcpu, X86_EFLAGS_FIXED);
-	kvm_rip_write(vcpu, 0x8000);
-
-	cr0 = vcpu->arch.cr0 & ~(X86_CR0_PE | X86_CR0_EM | X86_CR0_TS | X86_CR0_PG);
-	static_call(kvm_x86_set_cr0)(vcpu, cr0);
-	vcpu->arch.cr0 = cr0;
-
-	static_call(kvm_x86_set_cr4)(vcpu, 0);
-
-	/* Undocumented: IDT limit is set to zero on entry to SMM.  */
-	dt.address = dt.size = 0;
-	static_call(kvm_x86_set_idt)(vcpu, &dt);
-
-	kvm_set_dr(vcpu, 7, DR7_FIXED_1);
-
-	cs.selector = (vcpu->arch.smbase >> 4) & 0xffff;
-	cs.base = vcpu->arch.smbase;
-
-	ds.selector = 0;
-	ds.base = 0;
-
-	cs.limit    = ds.limit = 0xffffffff;
-	cs.type     = ds.type = 0x3;
-	cs.dpl      = ds.dpl = 0;
-	cs.db       = ds.db = 0;
-	cs.s        = ds.s = 1;
-	cs.l        = ds.l = 0;
-	cs.g        = ds.g = 1;
-	cs.avl      = ds.avl = 0;
-	cs.present  = ds.present = 1;
-	cs.unusable = ds.unusable = 0;
-	cs.padding  = ds.padding = 0;
-
-	kvm_set_segment(vcpu, &cs, VCPU_SREG_CS);
-	kvm_set_segment(vcpu, &ds, VCPU_SREG_DS);
-	kvm_set_segment(vcpu, &ds, VCPU_SREG_ES);
-	kvm_set_segment(vcpu, &ds, VCPU_SREG_FS);
-	kvm_set_segment(vcpu, &ds, VCPU_SREG_GS);
-	kvm_set_segment(vcpu, &ds, VCPU_SREG_SS);
-
-#ifdef CONFIG_X86_64
-	if (guest_cpuid_has(vcpu, X86_FEATURE_LM))
-		static_call(kvm_x86_set_efer)(vcpu, 0);
-#endif
-
-	kvm_update_cpuid_runtime(vcpu);
-	kvm_mmu_reset_context(vcpu);
-}
-
 void kvm_make_scan_ioapic_request_mask(struct kvm *kvm,
 				       unsigned long *vcpu_bitmap)
 {
-- 
2.31.1



^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH 03/10] KVM: x86: move SMM exit to a new file
  2022-10-27 16:49 [PATCH v3 0/10] KVM: x86: allow compiling out SMM support Paolo Bonzini
  2022-10-27 16:49 ` [PATCH 01/10] KVM: x86: start moving SMM-related functions to new files Paolo Bonzini
  2022-10-27 16:49 ` [PATCH 02/10] KVM: x86: move SMM entry to a new file Paolo Bonzini
@ 2022-10-27 16:49 ` Paolo Bonzini
  2022-10-27 16:49 ` [PATCH 04/10] KVM: x86: do not go through ctxt->ops when emulating rsm Paolo Bonzini
                   ` (6 subsequent siblings)
  9 siblings, 0 replies; 12+ messages in thread
From: Paolo Bonzini @ 2022-10-27 16:49 UTC (permalink / raw)
  To: linux-kernel, kvm; +Cc: mlevitsk, seanjc

Some users of KVM implement the UEFI variable store through a paravirtual
device that does not require the "SMM lockbox" component of edk2, and
would like to compile out system management mode.  In preparation for
that, move the SMM exit code out of emulate.c and into a new file.

The code is still written as a series of invocations of the emulator
callbacks, but the two exiting_smm and leave_smm callbacks are merged
into one, and all the code from em_rsm is now part of the callback.
This removes all knowledge of the format of the SMM save state area
from the emulator.  Further patches will clean up the code and
invoke KVM's own functions to access control registers, descriptor
caches, etc.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220929172016.319443-4-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/kvm/emulate.c     | 356 +------------------------------------
 arch/x86/kvm/kvm_emulate.h |  34 +++-
 arch/x86/kvm/smm.c         | 316 ++++++++++++++++++++++++++++++++
 arch/x86/kvm/smm.h         |   1 +
 arch/x86/kvm/x86.c         |  14 --
 5 files changed, 351 insertions(+), 370 deletions(-)

diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index de09660a61e5..671f7e5871ff 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -30,7 +30,6 @@
 #include "tss.h"
 #include "mmu.h"
 #include "pmu.h"
-#include "smm.h"
 
 /*
  * Operand types
@@ -243,37 +242,6 @@ enum x86_transfer_type {
 	X86_TRANSFER_TASK_SWITCH,
 };
 
-static ulong reg_read(struct x86_emulate_ctxt *ctxt, unsigned nr)
-{
-	if (KVM_EMULATOR_BUG_ON(nr >= NR_EMULATOR_GPRS, ctxt))
-		nr &= NR_EMULATOR_GPRS - 1;
-
-	if (!(ctxt->regs_valid & (1 << nr))) {
-		ctxt->regs_valid |= 1 << nr;
-		ctxt->_regs[nr] = ctxt->ops->read_gpr(ctxt, nr);
-	}
-	return ctxt->_regs[nr];
-}
-
-static ulong *reg_write(struct x86_emulate_ctxt *ctxt, unsigned nr)
-{
-	if (KVM_EMULATOR_BUG_ON(nr >= NR_EMULATOR_GPRS, ctxt))
-		nr &= NR_EMULATOR_GPRS - 1;
-
-	BUILD_BUG_ON(sizeof(ctxt->regs_dirty) * BITS_PER_BYTE < NR_EMULATOR_GPRS);
-	BUILD_BUG_ON(sizeof(ctxt->regs_valid) * BITS_PER_BYTE < NR_EMULATOR_GPRS);
-
-	ctxt->regs_valid |= 1 << nr;
-	ctxt->regs_dirty |= 1 << nr;
-	return &ctxt->_regs[nr];
-}
-
-static ulong *reg_rmw(struct x86_emulate_ctxt *ctxt, unsigned nr)
-{
-	reg_read(ctxt, nr);
-	return reg_write(ctxt, nr);
-}
-
 static void writeback_registers(struct x86_emulate_ctxt *ctxt)
 {
 	unsigned long dirty = ctxt->regs_dirty;
@@ -2310,334 +2278,14 @@ static int em_lseg(struct x86_emulate_ctxt *ctxt)
 	return rc;
 }
 
-static int emulator_has_longmode(struct x86_emulate_ctxt *ctxt)
-{
-#ifdef CONFIG_X86_64
-	return ctxt->ops->guest_has_long_mode(ctxt);
-#else
-	return false;
-#endif
-}
-
-static void rsm_set_desc_flags(struct desc_struct *desc, u32 flags)
-{
-	desc->g    = (flags >> 23) & 1;
-	desc->d    = (flags >> 22) & 1;
-	desc->l    = (flags >> 21) & 1;
-	desc->avl  = (flags >> 20) & 1;
-	desc->p    = (flags >> 15) & 1;
-	desc->dpl  = (flags >> 13) & 3;
-	desc->s    = (flags >> 12) & 1;
-	desc->type = (flags >>  8) & 15;
-}
-
-static int rsm_load_seg_32(struct x86_emulate_ctxt *ctxt, const char *smstate,
-			   int n)
-{
-	struct desc_struct desc;
-	int offset;
-	u16 selector;
-
-	selector = GET_SMSTATE(u32, smstate, 0x7fa8 + n * 4);
-
-	if (n < 3)
-		offset = 0x7f84 + n * 12;
-	else
-		offset = 0x7f2c + (n - 3) * 12;
-
-	set_desc_base(&desc,      GET_SMSTATE(u32, smstate, offset + 8));
-	set_desc_limit(&desc,     GET_SMSTATE(u32, smstate, offset + 4));
-	rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smstate, offset));
-	ctxt->ops->set_segment(ctxt, selector, &desc, 0, n);
-	return X86EMUL_CONTINUE;
-}
-
-#ifdef CONFIG_X86_64
-static int rsm_load_seg_64(struct x86_emulate_ctxt *ctxt, const char *smstate,
-			   int n)
-{
-	struct desc_struct desc;
-	int offset;
-	u16 selector;
-	u32 base3;
-
-	offset = 0x7e00 + n * 16;
-
-	selector =                GET_SMSTATE(u16, smstate, offset);
-	rsm_set_desc_flags(&desc, GET_SMSTATE(u16, smstate, offset + 2) << 8);
-	set_desc_limit(&desc,     GET_SMSTATE(u32, smstate, offset + 4));
-	set_desc_base(&desc,      GET_SMSTATE(u32, smstate, offset + 8));
-	base3 =                   GET_SMSTATE(u32, smstate, offset + 12);
-
-	ctxt->ops->set_segment(ctxt, selector, &desc, base3, n);
-	return X86EMUL_CONTINUE;
-}
-#endif
-
-static int rsm_enter_protected_mode(struct x86_emulate_ctxt *ctxt,
-				    u64 cr0, u64 cr3, u64 cr4)
-{
-	int bad;
-	u64 pcid;
-
-	/* In order to later set CR4.PCIDE, CR3[11:0] must be zero.  */
-	pcid = 0;
-	if (cr4 & X86_CR4_PCIDE) {
-		pcid = cr3 & 0xfff;
-		cr3 &= ~0xfff;
-	}
-
-	bad = ctxt->ops->set_cr(ctxt, 3, cr3);
-	if (bad)
-		return X86EMUL_UNHANDLEABLE;
-
-	/*
-	 * First enable PAE, long mode needs it before CR0.PG = 1 is set.
-	 * Then enable protected mode.	However, PCID cannot be enabled
-	 * if EFER.LMA=0, so set it separately.
-	 */
-	bad = ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PCIDE);
-	if (bad)
-		return X86EMUL_UNHANDLEABLE;
-
-	bad = ctxt->ops->set_cr(ctxt, 0, cr0);
-	if (bad)
-		return X86EMUL_UNHANDLEABLE;
-
-	if (cr4 & X86_CR4_PCIDE) {
-		bad = ctxt->ops->set_cr(ctxt, 4, cr4);
-		if (bad)
-			return X86EMUL_UNHANDLEABLE;
-		if (pcid) {
-			bad = ctxt->ops->set_cr(ctxt, 3, cr3 | pcid);
-			if (bad)
-				return X86EMUL_UNHANDLEABLE;
-		}
-
-	}
-
-	return X86EMUL_CONTINUE;
-}
-
-static int rsm_load_state_32(struct x86_emulate_ctxt *ctxt,
-			     const char *smstate)
-{
-	struct desc_struct desc;
-	struct desc_ptr dt;
-	u16 selector;
-	u32 val, cr0, cr3, cr4;
-	int i;
-
-	cr0 =                      GET_SMSTATE(u32, smstate, 0x7ffc);
-	cr3 =                      GET_SMSTATE(u32, smstate, 0x7ff8);
-	ctxt->eflags =             GET_SMSTATE(u32, smstate, 0x7ff4) | X86_EFLAGS_FIXED;
-	ctxt->_eip =               GET_SMSTATE(u32, smstate, 0x7ff0);
-
-	for (i = 0; i < NR_EMULATOR_GPRS; i++)
-		*reg_write(ctxt, i) = GET_SMSTATE(u32, smstate, 0x7fd0 + i * 4);
-
-	val = GET_SMSTATE(u32, smstate, 0x7fcc);
-
-	if (ctxt->ops->set_dr(ctxt, 6, val))
-		return X86EMUL_UNHANDLEABLE;
-
-	val = GET_SMSTATE(u32, smstate, 0x7fc8);
-
-	if (ctxt->ops->set_dr(ctxt, 7, val))
-		return X86EMUL_UNHANDLEABLE;
-
-	selector =                 GET_SMSTATE(u32, smstate, 0x7fc4);
-	set_desc_base(&desc,       GET_SMSTATE(u32, smstate, 0x7f64));
-	set_desc_limit(&desc,      GET_SMSTATE(u32, smstate, 0x7f60));
-	rsm_set_desc_flags(&desc,  GET_SMSTATE(u32, smstate, 0x7f5c));
-	ctxt->ops->set_segment(ctxt, selector, &desc, 0, VCPU_SREG_TR);
-
-	selector =                 GET_SMSTATE(u32, smstate, 0x7fc0);
-	set_desc_base(&desc,       GET_SMSTATE(u32, smstate, 0x7f80));
-	set_desc_limit(&desc,      GET_SMSTATE(u32, smstate, 0x7f7c));
-	rsm_set_desc_flags(&desc,  GET_SMSTATE(u32, smstate, 0x7f78));
-	ctxt->ops->set_segment(ctxt, selector, &desc, 0, VCPU_SREG_LDTR);
-
-	dt.address =               GET_SMSTATE(u32, smstate, 0x7f74);
-	dt.size =                  GET_SMSTATE(u32, smstate, 0x7f70);
-	ctxt->ops->set_gdt(ctxt, &dt);
-
-	dt.address =               GET_SMSTATE(u32, smstate, 0x7f58);
-	dt.size =                  GET_SMSTATE(u32, smstate, 0x7f54);
-	ctxt->ops->set_idt(ctxt, &dt);
-
-	for (i = 0; i < 6; i++) {
-		int r = rsm_load_seg_32(ctxt, smstate, i);
-		if (r != X86EMUL_CONTINUE)
-			return r;
-	}
-
-	cr4 = GET_SMSTATE(u32, smstate, 0x7f14);
-
-	ctxt->ops->set_smbase(ctxt, GET_SMSTATE(u32, smstate, 0x7ef8));
-
-	return rsm_enter_protected_mode(ctxt, cr0, cr3, cr4);
-}
-
-#ifdef CONFIG_X86_64
-static int rsm_load_state_64(struct x86_emulate_ctxt *ctxt,
-			     const char *smstate)
-{
-	struct desc_struct desc;
-	struct desc_ptr dt;
-	u64 val, cr0, cr3, cr4;
-	u32 base3;
-	u16 selector;
-	int i, r;
-
-	for (i = 0; i < NR_EMULATOR_GPRS; i++)
-		*reg_write(ctxt, i) = GET_SMSTATE(u64, smstate, 0x7ff8 - i * 8);
-
-	ctxt->_eip   = GET_SMSTATE(u64, smstate, 0x7f78);
-	ctxt->eflags = GET_SMSTATE(u32, smstate, 0x7f70) | X86_EFLAGS_FIXED;
-
-	val = GET_SMSTATE(u64, smstate, 0x7f68);
-
-	if (ctxt->ops->set_dr(ctxt, 6, val))
-		return X86EMUL_UNHANDLEABLE;
-
-	val = GET_SMSTATE(u64, smstate, 0x7f60);
-
-	if (ctxt->ops->set_dr(ctxt, 7, val))
-		return X86EMUL_UNHANDLEABLE;
-
-	cr0 =                       GET_SMSTATE(u64, smstate, 0x7f58);
-	cr3 =                       GET_SMSTATE(u64, smstate, 0x7f50);
-	cr4 =                       GET_SMSTATE(u64, smstate, 0x7f48);
-	ctxt->ops->set_smbase(ctxt, GET_SMSTATE(u32, smstate, 0x7f00));
-	val =                       GET_SMSTATE(u64, smstate, 0x7ed0);
-
-	if (ctxt->ops->set_msr(ctxt, MSR_EFER, val & ~EFER_LMA))
-		return X86EMUL_UNHANDLEABLE;
-
-	selector =                  GET_SMSTATE(u32, smstate, 0x7e90);
-	rsm_set_desc_flags(&desc,   GET_SMSTATE(u32, smstate, 0x7e92) << 8);
-	set_desc_limit(&desc,       GET_SMSTATE(u32, smstate, 0x7e94));
-	set_desc_base(&desc,        GET_SMSTATE(u32, smstate, 0x7e98));
-	base3 =                     GET_SMSTATE(u32, smstate, 0x7e9c);
-	ctxt->ops->set_segment(ctxt, selector, &desc, base3, VCPU_SREG_TR);
-
-	dt.size =                   GET_SMSTATE(u32, smstate, 0x7e84);
-	dt.address =                GET_SMSTATE(u64, smstate, 0x7e88);
-	ctxt->ops->set_idt(ctxt, &dt);
-
-	selector =                  GET_SMSTATE(u32, smstate, 0x7e70);
-	rsm_set_desc_flags(&desc,   GET_SMSTATE(u32, smstate, 0x7e72) << 8);
-	set_desc_limit(&desc,       GET_SMSTATE(u32, smstate, 0x7e74));
-	set_desc_base(&desc,        GET_SMSTATE(u32, smstate, 0x7e78));
-	base3 =                     GET_SMSTATE(u32, smstate, 0x7e7c);
-	ctxt->ops->set_segment(ctxt, selector, &desc, base3, VCPU_SREG_LDTR);
-
-	dt.size =                   GET_SMSTATE(u32, smstate, 0x7e64);
-	dt.address =                GET_SMSTATE(u64, smstate, 0x7e68);
-	ctxt->ops->set_gdt(ctxt, &dt);
-
-	r = rsm_enter_protected_mode(ctxt, cr0, cr3, cr4);
-	if (r != X86EMUL_CONTINUE)
-		return r;
-
-	for (i = 0; i < 6; i++) {
-		r = rsm_load_seg_64(ctxt, smstate, i);
-		if (r != X86EMUL_CONTINUE)
-			return r;
-	}
-
-	return X86EMUL_CONTINUE;
-}
-#endif
-
 static int em_rsm(struct x86_emulate_ctxt *ctxt)
 {
-	unsigned long cr0, cr4, efer;
-	char buf[512];
-	u64 smbase;
-	int ret;
-
 	if ((ctxt->ops->get_hflags(ctxt) & X86EMUL_SMM_MASK) == 0)
 		return emulate_ud(ctxt);
 
-	smbase = ctxt->ops->get_smbase(ctxt);
-
-	ret = ctxt->ops->read_phys(ctxt, smbase + 0xfe00, buf, sizeof(buf));
-	if (ret != X86EMUL_CONTINUE)
-		return X86EMUL_UNHANDLEABLE;
-
-	if ((ctxt->ops->get_hflags(ctxt) & X86EMUL_SMM_INSIDE_NMI_MASK) == 0)
-		ctxt->ops->set_nmi_mask(ctxt, false);
-
-	ctxt->ops->exiting_smm(ctxt);
-
-	/*
-	 * Get back to real mode, to prepare a safe state in which to load
-	 * CR0/CR3/CR4/EFER.  It's all a bit more complicated if the vCPU
-	 * supports long mode.
-	 */
-	if (emulator_has_longmode(ctxt)) {
-		struct desc_struct cs_desc;
-
-		/* Zero CR4.PCIDE before CR0.PG.  */
-		cr4 = ctxt->ops->get_cr(ctxt, 4);
-		if (cr4 & X86_CR4_PCIDE)
-			ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PCIDE);
-
-		/* A 32-bit code segment is required to clear EFER.LMA.  */
-		memset(&cs_desc, 0, sizeof(cs_desc));
-		cs_desc.type = 0xb;
-		cs_desc.s = cs_desc.g = cs_desc.p = 1;
-		ctxt->ops->set_segment(ctxt, 0, &cs_desc, 0, VCPU_SREG_CS);
-	}
-
-	/* For the 64-bit case, this will clear EFER.LMA.  */
-	cr0 = ctxt->ops->get_cr(ctxt, 0);
-	if (cr0 & X86_CR0_PE)
-		ctxt->ops->set_cr(ctxt, 0, cr0 & ~(X86_CR0_PG | X86_CR0_PE));
-
-	if (emulator_has_longmode(ctxt)) {
-		/* Clear CR4.PAE before clearing EFER.LME. */
-		cr4 = ctxt->ops->get_cr(ctxt, 4);
-		if (cr4 & X86_CR4_PAE)
-			ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PAE);
-
-		/* And finally go back to 32-bit mode.  */
-		efer = 0;
-		ctxt->ops->set_msr(ctxt, MSR_EFER, efer);
-	}
-
-	/*
-	 * Give leave_smm() a chance to make ISA-specific changes to the vCPU
-	 * state (e.g. enter guest mode) before loading state from the SMM
-	 * state-save area.
-	 */
-	if (ctxt->ops->leave_smm(ctxt, buf))
-		goto emulate_shutdown;
-
-#ifdef CONFIG_X86_64
-	if (emulator_has_longmode(ctxt))
-		ret = rsm_load_state_64(ctxt, buf);
-	else
-#endif
-		ret = rsm_load_state_32(ctxt, buf);
-
-	if (ret != X86EMUL_CONTINUE)
-		goto emulate_shutdown;
-
-	/*
-	 * Note, the ctxt->ops callbacks are responsible for handling side
-	 * effects when writing MSRs and CRs, e.g. MMU context resets, CPUID
-	 * runtime updates, etc...  If that changes, e.g. this flow is moved
-	 * out of the emulator to make it look more like enter_smm(), then
-	 * those side effects need to be explicitly handled for both success
-	 * and shutdown.
-	 */
-	return X86EMUL_CONTINUE;
+	if (ctxt->ops->leave_smm(ctxt))
+		ctxt->ops->triple_fault(ctxt);
 
-emulate_shutdown:
-	ctxt->ops->triple_fault(ctxt);
 	return X86EMUL_CONTINUE;
 }
 
diff --git a/arch/x86/kvm/kvm_emulate.h b/arch/x86/kvm/kvm_emulate.h
index 89246446d6aa..d7afbc448dd2 100644
--- a/arch/x86/kvm/kvm_emulate.h
+++ b/arch/x86/kvm/kvm_emulate.h
@@ -234,8 +234,7 @@ struct x86_emulate_ops {
 	void (*set_nmi_mask)(struct x86_emulate_ctxt *ctxt, bool masked);
 
 	unsigned (*get_hflags)(struct x86_emulate_ctxt *ctxt);
-	void (*exiting_smm)(struct x86_emulate_ctxt *ctxt);
-	int (*leave_smm)(struct x86_emulate_ctxt *ctxt, const char *smstate);
+	int (*leave_smm)(struct x86_emulate_ctxt *ctxt);
 	void (*triple_fault)(struct x86_emulate_ctxt *ctxt);
 	int (*set_xcr)(struct x86_emulate_ctxt *ctxt, u32 index, u64 xcr);
 };
@@ -526,4 +525,35 @@ void emulator_invalidate_register_cache(struct x86_emulate_ctxt *ctxt);
 void emulator_writeback_register_cache(struct x86_emulate_ctxt *ctxt);
 bool emulator_can_use_gpa(struct x86_emulate_ctxt *ctxt);
 
+static inline ulong reg_read(struct x86_emulate_ctxt *ctxt, unsigned nr)
+{
+	if (KVM_EMULATOR_BUG_ON(nr >= NR_EMULATOR_GPRS, ctxt))
+		nr &= NR_EMULATOR_GPRS - 1;
+
+	if (!(ctxt->regs_valid & (1 << nr))) {
+		ctxt->regs_valid |= 1 << nr;
+		ctxt->_regs[nr] = ctxt->ops->read_gpr(ctxt, nr);
+	}
+	return ctxt->_regs[nr];
+}
+
+static inline ulong *reg_write(struct x86_emulate_ctxt *ctxt, unsigned nr)
+{
+	if (KVM_EMULATOR_BUG_ON(nr >= NR_EMULATOR_GPRS, ctxt))
+		nr &= NR_EMULATOR_GPRS - 1;
+
+	BUILD_BUG_ON(sizeof(ctxt->regs_dirty) * BITS_PER_BYTE < NR_EMULATOR_GPRS);
+	BUILD_BUG_ON(sizeof(ctxt->regs_valid) * BITS_PER_BYTE < NR_EMULATOR_GPRS);
+
+	ctxt->regs_valid |= 1 << nr;
+	ctxt->regs_dirty |= 1 << nr;
+	return &ctxt->_regs[nr];
+}
+
+static inline ulong *reg_rmw(struct x86_emulate_ctxt *ctxt, unsigned nr)
+{
+	reg_read(ctxt, nr);
+	return reg_write(ctxt, nr);
+}
+
 #endif /* _ASM_X86_KVM_X86_EMULATE_H */
diff --git a/arch/x86/kvm/smm.c b/arch/x86/kvm/smm.c
index 26a6859e421f..773e07b6397d 100644
--- a/arch/x86/kvm/smm.c
+++ b/arch/x86/kvm/smm.c
@@ -270,3 +270,319 @@ void enter_smm(struct kvm_vcpu *vcpu)
 	kvm_update_cpuid_runtime(vcpu);
 	kvm_mmu_reset_context(vcpu);
 }
+
+static int emulator_has_longmode(struct x86_emulate_ctxt *ctxt)
+{
+#ifdef CONFIG_X86_64
+	return ctxt->ops->guest_has_long_mode(ctxt);
+#else
+	return false;
+#endif
+}
+
+static void rsm_set_desc_flags(struct desc_struct *desc, u32 flags)
+{
+	desc->g    = (flags >> 23) & 1;
+	desc->d    = (flags >> 22) & 1;
+	desc->l    = (flags >> 21) & 1;
+	desc->avl  = (flags >> 20) & 1;
+	desc->p    = (flags >> 15) & 1;
+	desc->dpl  = (flags >> 13) & 3;
+	desc->s    = (flags >> 12) & 1;
+	desc->type = (flags >>  8) & 15;
+}
+
+static int rsm_load_seg_32(struct x86_emulate_ctxt *ctxt, const char *smstate,
+			   int n)
+{
+	struct desc_struct desc;
+	int offset;
+	u16 selector;
+
+	selector = GET_SMSTATE(u32, smstate, 0x7fa8 + n * 4);
+
+	if (n < 3)
+		offset = 0x7f84 + n * 12;
+	else
+		offset = 0x7f2c + (n - 3) * 12;
+
+	set_desc_base(&desc,      GET_SMSTATE(u32, smstate, offset + 8));
+	set_desc_limit(&desc,     GET_SMSTATE(u32, smstate, offset + 4));
+	rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smstate, offset));
+	ctxt->ops->set_segment(ctxt, selector, &desc, 0, n);
+	return X86EMUL_CONTINUE;
+}
+
+#ifdef CONFIG_X86_64
+static int rsm_load_seg_64(struct x86_emulate_ctxt *ctxt, const char *smstate,
+			   int n)
+{
+	struct desc_struct desc;
+	int offset;
+	u16 selector;
+	u32 base3;
+
+	offset = 0x7e00 + n * 16;
+
+	selector =                GET_SMSTATE(u16, smstate, offset);
+	rsm_set_desc_flags(&desc, GET_SMSTATE(u16, smstate, offset + 2) << 8);
+	set_desc_limit(&desc,     GET_SMSTATE(u32, smstate, offset + 4));
+	set_desc_base(&desc,      GET_SMSTATE(u32, smstate, offset + 8));
+	base3 =                   GET_SMSTATE(u32, smstate, offset + 12);
+
+	ctxt->ops->set_segment(ctxt, selector, &desc, base3, n);
+	return X86EMUL_CONTINUE;
+}
+#endif
+
+static int rsm_enter_protected_mode(struct x86_emulate_ctxt *ctxt,
+				    u64 cr0, u64 cr3, u64 cr4)
+{
+	int bad;
+	u64 pcid;
+
+	/* In order to later set CR4.PCIDE, CR3[11:0] must be zero.  */
+	pcid = 0;
+	if (cr4 & X86_CR4_PCIDE) {
+		pcid = cr3 & 0xfff;
+		cr3 &= ~0xfff;
+	}
+
+	bad = ctxt->ops->set_cr(ctxt, 3, cr3);
+	if (bad)
+		return X86EMUL_UNHANDLEABLE;
+
+	/*
+	 * First enable PAE, long mode needs it before CR0.PG = 1 is set.
+	 * Then enable protected mode.	However, PCID cannot be enabled
+	 * if EFER.LMA=0, so set it separately.
+	 */
+	bad = ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PCIDE);
+	if (bad)
+		return X86EMUL_UNHANDLEABLE;
+
+	bad = ctxt->ops->set_cr(ctxt, 0, cr0);
+	if (bad)
+		return X86EMUL_UNHANDLEABLE;
+
+	if (cr4 & X86_CR4_PCIDE) {
+		bad = ctxt->ops->set_cr(ctxt, 4, cr4);
+		if (bad)
+			return X86EMUL_UNHANDLEABLE;
+		if (pcid) {
+			bad = ctxt->ops->set_cr(ctxt, 3, cr3 | pcid);
+			if (bad)
+				return X86EMUL_UNHANDLEABLE;
+		}
+
+	}
+
+	return X86EMUL_CONTINUE;
+}
+
+static int rsm_load_state_32(struct x86_emulate_ctxt *ctxt,
+			     const char *smstate)
+{
+	struct desc_struct desc;
+	struct desc_ptr dt;
+	u16 selector;
+	u32 val, cr0, cr3, cr4;
+	int i;
+
+	cr0 =                      GET_SMSTATE(u32, smstate, 0x7ffc);
+	cr3 =                      GET_SMSTATE(u32, smstate, 0x7ff8);
+	ctxt->eflags =             GET_SMSTATE(u32, smstate, 0x7ff4) | X86_EFLAGS_FIXED;
+	ctxt->_eip =               GET_SMSTATE(u32, smstate, 0x7ff0);
+
+	for (i = 0; i < NR_EMULATOR_GPRS; i++)
+		*reg_write(ctxt, i) = GET_SMSTATE(u32, smstate, 0x7fd0 + i * 4);
+
+	val = GET_SMSTATE(u32, smstate, 0x7fcc);
+
+	if (ctxt->ops->set_dr(ctxt, 6, val))
+		return X86EMUL_UNHANDLEABLE;
+
+	val = GET_SMSTATE(u32, smstate, 0x7fc8);
+
+	if (ctxt->ops->set_dr(ctxt, 7, val))
+		return X86EMUL_UNHANDLEABLE;
+
+	selector =                 GET_SMSTATE(u32, smstate, 0x7fc4);
+	set_desc_base(&desc,       GET_SMSTATE(u32, smstate, 0x7f64));
+	set_desc_limit(&desc,      GET_SMSTATE(u32, smstate, 0x7f60));
+	rsm_set_desc_flags(&desc,  GET_SMSTATE(u32, smstate, 0x7f5c));
+	ctxt->ops->set_segment(ctxt, selector, &desc, 0, VCPU_SREG_TR);
+
+	selector =                 GET_SMSTATE(u32, smstate, 0x7fc0);
+	set_desc_base(&desc,       GET_SMSTATE(u32, smstate, 0x7f80));
+	set_desc_limit(&desc,      GET_SMSTATE(u32, smstate, 0x7f7c));
+	rsm_set_desc_flags(&desc,  GET_SMSTATE(u32, smstate, 0x7f78));
+	ctxt->ops->set_segment(ctxt, selector, &desc, 0, VCPU_SREG_LDTR);
+
+	dt.address =               GET_SMSTATE(u32, smstate, 0x7f74);
+	dt.size =                  GET_SMSTATE(u32, smstate, 0x7f70);
+	ctxt->ops->set_gdt(ctxt, &dt);
+
+	dt.address =               GET_SMSTATE(u32, smstate, 0x7f58);
+	dt.size =                  GET_SMSTATE(u32, smstate, 0x7f54);
+	ctxt->ops->set_idt(ctxt, &dt);
+
+	for (i = 0; i < 6; i++) {
+		int r = rsm_load_seg_32(ctxt, smstate, i);
+		if (r != X86EMUL_CONTINUE)
+			return r;
+	}
+
+	cr4 = GET_SMSTATE(u32, smstate, 0x7f14);
+
+	ctxt->ops->set_smbase(ctxt, GET_SMSTATE(u32, smstate, 0x7ef8));
+
+	return rsm_enter_protected_mode(ctxt, cr0, cr3, cr4);
+}
+
+#ifdef CONFIG_X86_64
+static int rsm_load_state_64(struct x86_emulate_ctxt *ctxt,
+			     const char *smstate)
+{
+	struct desc_struct desc;
+	struct desc_ptr dt;
+	u64 val, cr0, cr3, cr4;
+	u32 base3;
+	u16 selector;
+	int i, r;
+
+	for (i = 0; i < NR_EMULATOR_GPRS; i++)
+		*reg_write(ctxt, i) = GET_SMSTATE(u64, smstate, 0x7ff8 - i * 8);
+
+	ctxt->_eip   = GET_SMSTATE(u64, smstate, 0x7f78);
+	ctxt->eflags = GET_SMSTATE(u32, smstate, 0x7f70) | X86_EFLAGS_FIXED;
+
+	val = GET_SMSTATE(u64, smstate, 0x7f68);
+
+	if (ctxt->ops->set_dr(ctxt, 6, val))
+		return X86EMUL_UNHANDLEABLE;
+
+	val = GET_SMSTATE(u64, smstate, 0x7f60);
+
+	if (ctxt->ops->set_dr(ctxt, 7, val))
+		return X86EMUL_UNHANDLEABLE;
+
+	cr0 =                       GET_SMSTATE(u64, smstate, 0x7f58);
+	cr3 =                       GET_SMSTATE(u64, smstate, 0x7f50);
+	cr4 =                       GET_SMSTATE(u64, smstate, 0x7f48);
+	ctxt->ops->set_smbase(ctxt, GET_SMSTATE(u32, smstate, 0x7f00));
+	val =                       GET_SMSTATE(u64, smstate, 0x7ed0);
+
+	if (ctxt->ops->set_msr(ctxt, MSR_EFER, val & ~EFER_LMA))
+		return X86EMUL_UNHANDLEABLE;
+
+	selector =                  GET_SMSTATE(u32, smstate, 0x7e90);
+	rsm_set_desc_flags(&desc,   GET_SMSTATE(u32, smstate, 0x7e92) << 8);
+	set_desc_limit(&desc,       GET_SMSTATE(u32, smstate, 0x7e94));
+	set_desc_base(&desc,        GET_SMSTATE(u32, smstate, 0x7e98));
+	base3 =                     GET_SMSTATE(u32, smstate, 0x7e9c);
+	ctxt->ops->set_segment(ctxt, selector, &desc, base3, VCPU_SREG_TR);
+
+	dt.size =                   GET_SMSTATE(u32, smstate, 0x7e84);
+	dt.address =                GET_SMSTATE(u64, smstate, 0x7e88);
+	ctxt->ops->set_idt(ctxt, &dt);
+
+	selector =                  GET_SMSTATE(u32, smstate, 0x7e70);
+	rsm_set_desc_flags(&desc,   GET_SMSTATE(u32, smstate, 0x7e72) << 8);
+	set_desc_limit(&desc,       GET_SMSTATE(u32, smstate, 0x7e74));
+	set_desc_base(&desc,        GET_SMSTATE(u32, smstate, 0x7e78));
+	base3 =                     GET_SMSTATE(u32, smstate, 0x7e7c);
+	ctxt->ops->set_segment(ctxt, selector, &desc, base3, VCPU_SREG_LDTR);
+
+	dt.size =                   GET_SMSTATE(u32, smstate, 0x7e64);
+	dt.address =                GET_SMSTATE(u64, smstate, 0x7e68);
+	ctxt->ops->set_gdt(ctxt, &dt);
+
+	r = rsm_enter_protected_mode(ctxt, cr0, cr3, cr4);
+	if (r != X86EMUL_CONTINUE)
+		return r;
+
+	for (i = 0; i < 6; i++) {
+		r = rsm_load_seg_64(ctxt, smstate, i);
+		if (r != X86EMUL_CONTINUE)
+			return r;
+	}
+
+	return X86EMUL_CONTINUE;
+}
+#endif
+
+int emulator_leave_smm(struct x86_emulate_ctxt *ctxt)
+{
+	struct kvm_vcpu *vcpu = ctxt->vcpu;
+	unsigned long cr0, cr4, efer;
+	char buf[512];
+	u64 smbase;
+	int ret;
+
+	smbase = ctxt->ops->get_smbase(ctxt);
+
+	ret = ctxt->ops->read_phys(ctxt, smbase + 0xfe00, buf, sizeof(buf));
+	if (ret != X86EMUL_CONTINUE)
+		return X86EMUL_UNHANDLEABLE;
+
+	if ((ctxt->ops->get_hflags(ctxt) & X86EMUL_SMM_INSIDE_NMI_MASK) == 0)
+		ctxt->ops->set_nmi_mask(ctxt, false);
+
+	kvm_smm_changed(vcpu, false);
+
+	/*
+	 * Get back to real mode, to prepare a safe state in which to load
+	 * CR0/CR3/CR4/EFER.  It's all a bit more complicated if the vCPU
+	 * supports long mode.
+	 *
+	 * The ctxt->ops callbacks will handle all side effects when writing
+	 * writing MSRs and CRs, e.g. MMU context resets, CPUID
+	 * runtime updates, etc.
+	 */
+	if (emulator_has_longmode(ctxt)) {
+		struct desc_struct cs_desc;
+
+		/* Zero CR4.PCIDE before CR0.PG.  */
+		cr4 = ctxt->ops->get_cr(ctxt, 4);
+		if (cr4 & X86_CR4_PCIDE)
+			ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PCIDE);
+
+		/* A 32-bit code segment is required to clear EFER.LMA.  */
+		memset(&cs_desc, 0, sizeof(cs_desc));
+		cs_desc.type = 0xb;
+		cs_desc.s = cs_desc.g = cs_desc.p = 1;
+		ctxt->ops->set_segment(ctxt, 0, &cs_desc, 0, VCPU_SREG_CS);
+	}
+
+	/* For the 64-bit case, this will clear EFER.LMA.  */
+	cr0 = ctxt->ops->get_cr(ctxt, 0);
+	if (cr0 & X86_CR0_PE)
+		ctxt->ops->set_cr(ctxt, 0, cr0 & ~(X86_CR0_PG | X86_CR0_PE));
+
+	if (emulator_has_longmode(ctxt)) {
+		/* Clear CR4.PAE before clearing EFER.LME. */
+		cr4 = ctxt->ops->get_cr(ctxt, 4);
+		if (cr4 & X86_CR4_PAE)
+			ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PAE);
+
+		/* And finally go back to 32-bit mode.  */
+		efer = 0;
+		ctxt->ops->set_msr(ctxt, MSR_EFER, efer);
+	}
+
+	/*
+	 * Give leave_smm() a chance to make ISA-specific changes to the vCPU
+	 * state (e.g. enter guest mode) before loading state from the SMM
+	 * state-save area.
+	 */
+	if (static_call(kvm_x86_leave_smm)(vcpu, buf))
+		return X86EMUL_UNHANDLEABLE;
+
+#ifdef CONFIG_X86_64
+	if (emulator_has_longmode(ctxt))
+		return rsm_load_state_64(ctxt, buf);
+	else
+#endif
+		return rsm_load_state_32(ctxt, buf);
+}
diff --git a/arch/x86/kvm/smm.h b/arch/x86/kvm/smm.h
index aacc6dac2c99..b0602a92e511 100644
--- a/arch/x86/kvm/smm.h
+++ b/arch/x86/kvm/smm.h
@@ -21,6 +21,7 @@ static inline bool is_smm(struct kvm_vcpu *vcpu)
 
 void kvm_smm_changed(struct kvm_vcpu *vcpu, bool in_smm);
 void enter_smm(struct kvm_vcpu *vcpu);
+int emulator_leave_smm(struct x86_emulate_ctxt *ctxt);
 void process_smi(struct kvm_vcpu *vcpu);
 
 #endif
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index a03712d00883..676efc3d58ec 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -8149,19 +8149,6 @@ static unsigned emulator_get_hflags(struct x86_emulate_ctxt *ctxt)
 	return emul_to_vcpu(ctxt)->arch.hflags;
 }
 
-static void emulator_exiting_smm(struct x86_emulate_ctxt *ctxt)
-{
-	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
-
-	kvm_smm_changed(vcpu, false);
-}
-
-static int emulator_leave_smm(struct x86_emulate_ctxt *ctxt,
-				  const char *smstate)
-{
-	return static_call(kvm_x86_leave_smm)(emul_to_vcpu(ctxt), smstate);
-}
-
 static void emulator_triple_fault(struct x86_emulate_ctxt *ctxt)
 {
 	kvm_make_request(KVM_REQ_TRIPLE_FAULT, emul_to_vcpu(ctxt));
@@ -8225,7 +8212,6 @@ static const struct x86_emulate_ops emulate_ops = {
 	.guest_has_rdpid     = emulator_guest_has_rdpid,
 	.set_nmi_mask        = emulator_set_nmi_mask,
 	.get_hflags          = emulator_get_hflags,
-	.exiting_smm         = emulator_exiting_smm,
 	.leave_smm           = emulator_leave_smm,
 	.triple_fault        = emulator_triple_fault,
 	.set_xcr             = emulator_set_xcr,
-- 
2.31.1



^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH 04/10] KVM: x86: do not go through ctxt->ops when emulating rsm
  2022-10-27 16:49 [PATCH v3 0/10] KVM: x86: allow compiling out SMM support Paolo Bonzini
                   ` (2 preceding siblings ...)
  2022-10-27 16:49 ` [PATCH 03/10] KVM: x86: move SMM exit " Paolo Bonzini
@ 2022-10-27 16:49 ` Paolo Bonzini
       [not found]   ` <202210281538.c5NukqBx-lkp@intel.com>
  2022-10-27 16:49 ` [PATCH 05/10] KVM: allow compiling out SMM support Paolo Bonzini
                   ` (5 subsequent siblings)
  9 siblings, 1 reply; 12+ messages in thread
From: Paolo Bonzini @ 2022-10-27 16:49 UTC (permalink / raw)
  To: linux-kernel, kvm; +Cc: mlevitsk, seanjc

Now that RSM is implemented in a single emulator callback, there is no
point in going through other callbacks for the sake of modifying
processor state.  Just invoke KVM's own internal functions directly,
and remove the callbacks that were only used by em_rsm; the only
substantial difference is in the handling of the segment registers
and descriptor cache, which have to be parsed into a struct kvm_segment
instead of a struct desc_struct.

This also fixes a bug where emulator_set_segment was shifting the
limit left by 12 if the G bit is set, but the limit had not been
shifted right upon entry to SMM.

The emulator context is still used to restore EIP and the general
purpose registers.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220929172016.319443-5-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/kvm/kvm_emulate.h |  13 ---
 arch/x86/kvm/smm.c         | 177 +++++++++++++++++--------------------
 arch/x86/kvm/x86.c         |  33 -------
 3 files changed, 81 insertions(+), 142 deletions(-)

diff --git a/arch/x86/kvm/kvm_emulate.h b/arch/x86/kvm/kvm_emulate.h
index d7afbc448dd2..84b1f2661463 100644
--- a/arch/x86/kvm/kvm_emulate.h
+++ b/arch/x86/kvm/kvm_emulate.h
@@ -116,16 +116,6 @@ struct x86_emulate_ops {
 			unsigned int bytes,
 			struct x86_exception *fault, bool system);
 
-	/*
-	 * read_phys: Read bytes of standard (non-emulated/special) memory.
-	 *            Used for descriptor reading.
-	 *  @addr:  [IN ] Physical address from which to read.
-	 *  @val:   [OUT] Value read from memory.
-	 *  @bytes: [IN ] Number of bytes to read from memory.
-	 */
-	int (*read_phys)(struct x86_emulate_ctxt *ctxt, unsigned long addr,
-			void *val, unsigned int bytes);
-
 	/*
 	 * write_std: Write bytes of standard (non-emulated/special) memory.
 	 *            Used for descriptor writing.
@@ -209,11 +199,8 @@ struct x86_emulate_ops {
 	int (*cpl)(struct x86_emulate_ctxt *ctxt);
 	void (*get_dr)(struct x86_emulate_ctxt *ctxt, int dr, ulong *dest);
 	int (*set_dr)(struct x86_emulate_ctxt *ctxt, int dr, ulong value);
-	u64 (*get_smbase)(struct x86_emulate_ctxt *ctxt);
-	void (*set_smbase)(struct x86_emulate_ctxt *ctxt, u64 smbase);
 	int (*set_msr_with_filter)(struct x86_emulate_ctxt *ctxt, u32 msr_index, u64 data);
 	int (*get_msr_with_filter)(struct x86_emulate_ctxt *ctxt, u32 msr_index, u64 *pdata);
-	int (*set_msr)(struct x86_emulate_ctxt *ctxt, u32 msr_index, u64 data);
 	int (*get_msr)(struct x86_emulate_ctxt *ctxt, u32 msr_index, u64 *pdata);
 	int (*check_pmc)(struct x86_emulate_ctxt *ctxt, u32 pmc);
 	int (*read_pmc)(struct x86_emulate_ctxt *ctxt, u32 pmc, u64 *pdata);
diff --git a/arch/x86/kvm/smm.c b/arch/x86/kvm/smm.c
index 773e07b6397d..41ca128478fc 100644
--- a/arch/x86/kvm/smm.c
+++ b/arch/x86/kvm/smm.c
@@ -271,71 +271,59 @@ void enter_smm(struct kvm_vcpu *vcpu)
 	kvm_mmu_reset_context(vcpu);
 }
 
-static int emulator_has_longmode(struct x86_emulate_ctxt *ctxt)
-{
-#ifdef CONFIG_X86_64
-	return ctxt->ops->guest_has_long_mode(ctxt);
-#else
-	return false;
-#endif
-}
-
-static void rsm_set_desc_flags(struct desc_struct *desc, u32 flags)
+static void rsm_set_desc_flags(struct kvm_segment *desc, u32 flags)
 {
 	desc->g    = (flags >> 23) & 1;
-	desc->d    = (flags >> 22) & 1;
+	desc->db   = (flags >> 22) & 1;
 	desc->l    = (flags >> 21) & 1;
 	desc->avl  = (flags >> 20) & 1;
-	desc->p    = (flags >> 15) & 1;
+	desc->present = (flags >> 15) & 1;
 	desc->dpl  = (flags >> 13) & 3;
 	desc->s    = (flags >> 12) & 1;
 	desc->type = (flags >>  8) & 15;
+
+	desc->unusable = !desc->present;
+	desc->padding = 0;
 }
 
-static int rsm_load_seg_32(struct x86_emulate_ctxt *ctxt, const char *smstate,
+static int rsm_load_seg_32(struct kvm_vcpu *vcpu, const char *smstate,
 			   int n)
 {
-	struct desc_struct desc;
+	struct kvm_segment desc;
 	int offset;
-	u16 selector;
-
-	selector = GET_SMSTATE(u32, smstate, 0x7fa8 + n * 4);
 
 	if (n < 3)
 		offset = 0x7f84 + n * 12;
 	else
 		offset = 0x7f2c + (n - 3) * 12;
 
-	set_desc_base(&desc,      GET_SMSTATE(u32, smstate, offset + 8));
-	set_desc_limit(&desc,     GET_SMSTATE(u32, smstate, offset + 4));
+	desc.selector =           GET_SMSTATE(u32, smstate, 0x7fa8 + n * 4);
+	desc.base =               GET_SMSTATE(u32, smstate, offset + 8);
+	desc.limit =              GET_SMSTATE(u32, smstate, offset + 4);
 	rsm_set_desc_flags(&desc, GET_SMSTATE(u32, smstate, offset));
-	ctxt->ops->set_segment(ctxt, selector, &desc, 0, n);
+	kvm_set_segment(vcpu, &desc, n);
 	return X86EMUL_CONTINUE;
 }
 
 #ifdef CONFIG_X86_64
-static int rsm_load_seg_64(struct x86_emulate_ctxt *ctxt, const char *smstate,
+static int rsm_load_seg_64(struct kvm_vcpu *vcpu, const char *smstate,
 			   int n)
 {
-	struct desc_struct desc;
+	struct kvm_segment desc;
 	int offset;
-	u16 selector;
-	u32 base3;
 
 	offset = 0x7e00 + n * 16;
 
-	selector =                GET_SMSTATE(u16, smstate, offset);
+	desc.selector =           GET_SMSTATE(u16, smstate, offset);
 	rsm_set_desc_flags(&desc, GET_SMSTATE(u16, smstate, offset + 2) << 8);
-	set_desc_limit(&desc,     GET_SMSTATE(u32, smstate, offset + 4));
-	set_desc_base(&desc,      GET_SMSTATE(u32, smstate, offset + 8));
-	base3 =                   GET_SMSTATE(u32, smstate, offset + 12);
-
-	ctxt->ops->set_segment(ctxt, selector, &desc, base3, n);
+	desc.limit =              GET_SMSTATE(u32, smstate, offset + 4);
+	desc.base =               GET_SMSTATE(u64, smstate, offset + 8);
+	kvm_set_segment(vcpu, &desc, n);
 	return X86EMUL_CONTINUE;
 }
 #endif
 
-static int rsm_enter_protected_mode(struct x86_emulate_ctxt *ctxt,
+static int rsm_enter_protected_mode(struct kvm_vcpu *vcpu,
 				    u64 cr0, u64 cr3, u64 cr4)
 {
 	int bad;
@@ -348,7 +336,7 @@ static int rsm_enter_protected_mode(struct x86_emulate_ctxt *ctxt,
 		cr3 &= ~0xfff;
 	}
 
-	bad = ctxt->ops->set_cr(ctxt, 3, cr3);
+	bad = kvm_set_cr3(vcpu, cr3);
 	if (bad)
 		return X86EMUL_UNHANDLEABLE;
 
@@ -357,20 +345,20 @@ static int rsm_enter_protected_mode(struct x86_emulate_ctxt *ctxt,
 	 * Then enable protected mode.	However, PCID cannot be enabled
 	 * if EFER.LMA=0, so set it separately.
 	 */
-	bad = ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PCIDE);
+	bad = kvm_set_cr4(vcpu, cr4 & ~X86_CR4_PCIDE);
 	if (bad)
 		return X86EMUL_UNHANDLEABLE;
 
-	bad = ctxt->ops->set_cr(ctxt, 0, cr0);
+	bad = kvm_set_cr0(vcpu, cr0);
 	if (bad)
 		return X86EMUL_UNHANDLEABLE;
 
 	if (cr4 & X86_CR4_PCIDE) {
-		bad = ctxt->ops->set_cr(ctxt, 4, cr4);
+		bad = kvm_set_cr4(vcpu, cr4);
 		if (bad)
 			return X86EMUL_UNHANDLEABLE;
 		if (pcid) {
-			bad = ctxt->ops->set_cr(ctxt, 3, cr3 | pcid);
+			bad = kvm_set_cr3(vcpu, cr3 | pcid);
 			if (bad)
 				return X86EMUL_UNHANDLEABLE;
 		}
@@ -383,9 +371,9 @@ static int rsm_enter_protected_mode(struct x86_emulate_ctxt *ctxt,
 static int rsm_load_state_32(struct x86_emulate_ctxt *ctxt,
 			     const char *smstate)
 {
-	struct desc_struct desc;
+	struct kvm_vcpu *vcpu = ctxt->vcpu;
+	struct kvm_segment desc;
 	struct desc_ptr dt;
-	u16 selector;
 	u32 val, cr0, cr3, cr4;
 	int i;
 
@@ -399,56 +387,55 @@ static int rsm_load_state_32(struct x86_emulate_ctxt *ctxt,
 
 	val = GET_SMSTATE(u32, smstate, 0x7fcc);
 
-	if (ctxt->ops->set_dr(ctxt, 6, val))
+	if (kvm_set_dr(vcpu, 6, val))
 		return X86EMUL_UNHANDLEABLE;
 
 	val = GET_SMSTATE(u32, smstate, 0x7fc8);
 
-	if (ctxt->ops->set_dr(ctxt, 7, val))
+	if (kvm_set_dr(vcpu, 7, val))
 		return X86EMUL_UNHANDLEABLE;
 
-	selector =                 GET_SMSTATE(u32, smstate, 0x7fc4);
-	set_desc_base(&desc,       GET_SMSTATE(u32, smstate, 0x7f64));
-	set_desc_limit(&desc,      GET_SMSTATE(u32, smstate, 0x7f60));
+	desc.selector =            GET_SMSTATE(u32, smstate, 0x7fc4);
+	desc.base =                GET_SMSTATE(u32, smstate, 0x7f64);
+	desc.limit =               GET_SMSTATE(u32, smstate, 0x7f60);
 	rsm_set_desc_flags(&desc,  GET_SMSTATE(u32, smstate, 0x7f5c));
-	ctxt->ops->set_segment(ctxt, selector, &desc, 0, VCPU_SREG_TR);
+	kvm_set_segment(vcpu, &desc, VCPU_SREG_TR);
 
-	selector =                 GET_SMSTATE(u32, smstate, 0x7fc0);
-	set_desc_base(&desc,       GET_SMSTATE(u32, smstate, 0x7f80));
-	set_desc_limit(&desc,      GET_SMSTATE(u32, smstate, 0x7f7c));
+	desc.selector =            GET_SMSTATE(u32, smstate, 0x7fc0);
+	desc.base =                GET_SMSTATE(u32, smstate, 0x7f80);
+	desc.limit =               GET_SMSTATE(u32, smstate, 0x7f7c);
 	rsm_set_desc_flags(&desc,  GET_SMSTATE(u32, smstate, 0x7f78));
-	ctxt->ops->set_segment(ctxt, selector, &desc, 0, VCPU_SREG_LDTR);
+	kvm_set_segment(vcpu, &desc, VCPU_SREG_LDTR);
 
 	dt.address =               GET_SMSTATE(u32, smstate, 0x7f74);
 	dt.size =                  GET_SMSTATE(u32, smstate, 0x7f70);
-	ctxt->ops->set_gdt(ctxt, &dt);
+	static_call(kvm_x86_set_gdt)(vcpu, &dt);
 
 	dt.address =               GET_SMSTATE(u32, smstate, 0x7f58);
 	dt.size =                  GET_SMSTATE(u32, smstate, 0x7f54);
-	ctxt->ops->set_idt(ctxt, &dt);
+	static_call(kvm_x86_set_idt)(vcpu, &dt);
 
 	for (i = 0; i < 6; i++) {
-		int r = rsm_load_seg_32(ctxt, smstate, i);
+		int r = rsm_load_seg_32(vcpu, smstate, i);
 		if (r != X86EMUL_CONTINUE)
 			return r;
 	}
 
 	cr4 = GET_SMSTATE(u32, smstate, 0x7f14);
 
-	ctxt->ops->set_smbase(ctxt, GET_SMSTATE(u32, smstate, 0x7ef8));
+	vcpu->arch.smbase = GET_SMSTATE(u32, smstate, 0x7ef8);
 
-	return rsm_enter_protected_mode(ctxt, cr0, cr3, cr4);
+	return rsm_enter_protected_mode(vcpu, cr0, cr3, cr4);
 }
 
 #ifdef CONFIG_X86_64
 static int rsm_load_state_64(struct x86_emulate_ctxt *ctxt,
 			     const char *smstate)
 {
-	struct desc_struct desc;
+	struct kvm_vcpu *vcpu = ctxt->vcpu;
+	struct kvm_segment desc;
 	struct desc_ptr dt;
 	u64 val, cr0, cr3, cr4;
-	u32 base3;
-	u16 selector;
 	int i, r;
 
 	for (i = 0; i < NR_EMULATOR_GPRS; i++)
@@ -459,51 +446,49 @@ static int rsm_load_state_64(struct x86_emulate_ctxt *ctxt,
 
 	val = GET_SMSTATE(u64, smstate, 0x7f68);
 
-	if (ctxt->ops->set_dr(ctxt, 6, val))
+	if (kvm_set_dr(vcpu, 6, val))
 		return X86EMUL_UNHANDLEABLE;
 
 	val = GET_SMSTATE(u64, smstate, 0x7f60);
 
-	if (ctxt->ops->set_dr(ctxt, 7, val))
+	if (kvm_set_dr(vcpu, 7, val))
 		return X86EMUL_UNHANDLEABLE;
 
 	cr0 =                       GET_SMSTATE(u64, smstate, 0x7f58);
 	cr3 =                       GET_SMSTATE(u64, smstate, 0x7f50);
 	cr4 =                       GET_SMSTATE(u64, smstate, 0x7f48);
-	ctxt->ops->set_smbase(ctxt, GET_SMSTATE(u32, smstate, 0x7f00));
+	vcpu->arch.smbase =         GET_SMSTATE(u32, smstate, 0x7f00);
 	val =                       GET_SMSTATE(u64, smstate, 0x7ed0);
 
-	if (ctxt->ops->set_msr(ctxt, MSR_EFER, val & ~EFER_LMA))
+	if (kvm_set_msr(vcpu, MSR_EFER, val & ~EFER_LMA))
 		return X86EMUL_UNHANDLEABLE;
 
-	selector =                  GET_SMSTATE(u32, smstate, 0x7e90);
+	desc.selector =             GET_SMSTATE(u32, smstate, 0x7e90);
 	rsm_set_desc_flags(&desc,   GET_SMSTATE(u32, smstate, 0x7e92) << 8);
-	set_desc_limit(&desc,       GET_SMSTATE(u32, smstate, 0x7e94));
-	set_desc_base(&desc,        GET_SMSTATE(u32, smstate, 0x7e98));
-	base3 =                     GET_SMSTATE(u32, smstate, 0x7e9c);
-	ctxt->ops->set_segment(ctxt, selector, &desc, base3, VCPU_SREG_TR);
+	desc.limit =                GET_SMSTATE(u32, smstate, 0x7e94);
+	desc.base =                 GET_SMSTATE(u64, smstate, 0x7e98);
+	kvm_set_segment(vcpu, &desc, VCPU_SREG_TR);
 
 	dt.size =                   GET_SMSTATE(u32, smstate, 0x7e84);
 	dt.address =                GET_SMSTATE(u64, smstate, 0x7e88);
-	ctxt->ops->set_idt(ctxt, &dt);
+	static_call(kvm_x86_set_idt)(vcpu, &dt);
 
-	selector =                  GET_SMSTATE(u32, smstate, 0x7e70);
+	desc.selector =             GET_SMSTATE(u32, smstate, 0x7e70);
 	rsm_set_desc_flags(&desc,   GET_SMSTATE(u32, smstate, 0x7e72) << 8);
-	set_desc_limit(&desc,       GET_SMSTATE(u32, smstate, 0x7e74));
-	set_desc_base(&desc,        GET_SMSTATE(u32, smstate, 0x7e78));
-	base3 =                     GET_SMSTATE(u32, smstate, 0x7e7c);
-	ctxt->ops->set_segment(ctxt, selector, &desc, base3, VCPU_SREG_LDTR);
+	desc.limit =                GET_SMSTATE(u32, smstate, 0x7e74);
+	desc.base =                 GET_SMSTATE(u64, smstate, 0x7e78);
+	kvm_set_segment(vcpu, &desc, VCPU_SREG_LDTR);
 
 	dt.size =                   GET_SMSTATE(u32, smstate, 0x7e64);
 	dt.address =                GET_SMSTATE(u64, smstate, 0x7e68);
-	ctxt->ops->set_gdt(ctxt, &dt);
+	static_call(kvm_x86_set_gdt)(vcpu, &dt);
 
-	r = rsm_enter_protected_mode(ctxt, cr0, cr3, cr4);
+	r = rsm_enter_protected_mode(vcpu, cr0, cr3, cr4);
 	if (r != X86EMUL_CONTINUE)
 		return r;
 
 	for (i = 0; i < 6; i++) {
-		r = rsm_load_seg_64(ctxt, smstate, i);
+		r = rsm_load_seg_64(vcpu, smstate, i);
 		if (r != X86EMUL_CONTINUE)
 			return r;
 	}
@@ -520,14 +505,14 @@ int emulator_leave_smm(struct x86_emulate_ctxt *ctxt)
 	u64 smbase;
 	int ret;
 
-	smbase = ctxt->ops->get_smbase(ctxt);
+	smbase = vcpu->arch.smbase;
 
-	ret = ctxt->ops->read_phys(ctxt, smbase + 0xfe00, buf, sizeof(buf));
-	if (ret != X86EMUL_CONTINUE)
+	ret = kvm_vcpu_read_guest(vcpu, smbase + 0xfe00, buf, sizeof(buf));
+	if (ret < 0)
 		return X86EMUL_UNHANDLEABLE;
 
-	if ((ctxt->ops->get_hflags(ctxt) & X86EMUL_SMM_INSIDE_NMI_MASK) == 0)
-		ctxt->ops->set_nmi_mask(ctxt, false);
+	if ((vcpu->arch.hflags & HF_SMM_INSIDE_NMI_MASK) == 0)
+		static_call(kvm_x86_set_nmi_mask)(vcpu, false);
 
 	kvm_smm_changed(vcpu, false);
 
@@ -535,41 +520,41 @@ int emulator_leave_smm(struct x86_emulate_ctxt *ctxt)
 	 * Get back to real mode, to prepare a safe state in which to load
 	 * CR0/CR3/CR4/EFER.  It's all a bit more complicated if the vCPU
 	 * supports long mode.
-	 *
-	 * The ctxt->ops callbacks will handle all side effects when writing
-	 * writing MSRs and CRs, e.g. MMU context resets, CPUID
-	 * runtime updates, etc.
 	 */
-	if (emulator_has_longmode(ctxt)) {
-		struct desc_struct cs_desc;
+#ifdef CONFIG_X86_64
+	if (guest_cpuid_has(vcpu, X86_FEATURE_LM)) {
+		struct kvm_segment cs_desc;
 
 		/* Zero CR4.PCIDE before CR0.PG.  */
-		cr4 = ctxt->ops->get_cr(ctxt, 4);
+		cr4 = kvm_read_cr4(vcpu);
 		if (cr4 & X86_CR4_PCIDE)
-			ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PCIDE);
+			kvm_set_cr4(vcpu, cr4 & ~X86_CR4_PCIDE);
 
 		/* A 32-bit code segment is required to clear EFER.LMA.  */
 		memset(&cs_desc, 0, sizeof(cs_desc));
 		cs_desc.type = 0xb;
-		cs_desc.s = cs_desc.g = cs_desc.p = 1;
-		ctxt->ops->set_segment(ctxt, 0, &cs_desc, 0, VCPU_SREG_CS);
+		cs_desc.s = cs_desc.g = cs_desc.present = 1;
+		kvm_set_segment(vcpu, &cs_desc, VCPU_SREG_CS);
 	}
+#endif
 
 	/* For the 64-bit case, this will clear EFER.LMA.  */
-	cr0 = ctxt->ops->get_cr(ctxt, 0);
+	cr0 = kvm_read_cr0(vcpu);
 	if (cr0 & X86_CR0_PE)
-		ctxt->ops->set_cr(ctxt, 0, cr0 & ~(X86_CR0_PG | X86_CR0_PE));
+		kvm_set_cr0(vcpu, cr0 & ~(X86_CR0_PG | X86_CR0_PE));
 
-	if (emulator_has_longmode(ctxt)) {
+#ifdef CONFIG_X86_64
+	if (guest_cpuid_has(vcpu, X86_FEATURE_LM)) {
 		/* Clear CR4.PAE before clearing EFER.LME. */
-		cr4 = ctxt->ops->get_cr(ctxt, 4);
+		cr4 = kvm_read_cr4(vcpu);
 		if (cr4 & X86_CR4_PAE)
-			ctxt->ops->set_cr(ctxt, 4, cr4 & ~X86_CR4_PAE);
+			kvm_set_cr4(vcpu, cr4 & ~X86_CR4_PAE);
 
 		/* And finally go back to 32-bit mode.  */
 		efer = 0;
-		ctxt->ops->set_msr(ctxt, MSR_EFER, efer);
+		kvm_set_msr(vcpu, MSR_EFER, efer);
 	}
+#endif
 
 	/*
 	 * Give leave_smm() a chance to make ISA-specific changes to the vCPU
@@ -580,7 +565,7 @@ int emulator_leave_smm(struct x86_emulate_ctxt *ctxt)
 		return X86EMUL_UNHANDLEABLE;
 
 #ifdef CONFIG_X86_64
-	if (emulator_has_longmode(ctxt))
+	if (guest_cpuid_has(vcpu, X86_FEATURE_LM))
 		return rsm_load_state_64(ctxt, buf);
 	else
 #endif
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 676efc3d58ec..ec5e9a837a12 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -7255,15 +7255,6 @@ static int emulator_read_std(struct x86_emulate_ctxt *ctxt,
 	return kvm_read_guest_virt_helper(addr, val, bytes, vcpu, access, exception);
 }
 
-static int kvm_read_guest_phys_system(struct x86_emulate_ctxt *ctxt,
-		unsigned long addr, void *val, unsigned int bytes)
-{
-	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
-	int r = kvm_vcpu_read_guest(vcpu, addr, val, bytes);
-
-	return r < 0 ? X86EMUL_IO_NEEDED : X86EMUL_CONTINUE;
-}
-
 static int kvm_write_guest_virt_helper(gva_t addr, void *val, unsigned int bytes,
 				      struct kvm_vcpu *vcpu, u64 access,
 				      struct x86_exception *exception)
@@ -8055,26 +8046,6 @@ static int emulator_get_msr(struct x86_emulate_ctxt *ctxt,
 	return kvm_get_msr(emul_to_vcpu(ctxt), msr_index, pdata);
 }
 
-static int emulator_set_msr(struct x86_emulate_ctxt *ctxt,
-			    u32 msr_index, u64 data)
-{
-	return kvm_set_msr(emul_to_vcpu(ctxt), msr_index, data);
-}
-
-static u64 emulator_get_smbase(struct x86_emulate_ctxt *ctxt)
-{
-	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
-
-	return vcpu->arch.smbase;
-}
-
-static void emulator_set_smbase(struct x86_emulate_ctxt *ctxt, u64 smbase)
-{
-	struct kvm_vcpu *vcpu = emul_to_vcpu(ctxt);
-
-	vcpu->arch.smbase = smbase;
-}
-
 static int emulator_check_pmc(struct x86_emulate_ctxt *ctxt,
 			      u32 pmc)
 {
@@ -8173,7 +8144,6 @@ static const struct x86_emulate_ops emulate_ops = {
 	.write_gpr           = emulator_write_gpr,
 	.read_std            = emulator_read_std,
 	.write_std           = emulator_write_std,
-	.read_phys           = kvm_read_guest_phys_system,
 	.fetch               = kvm_fetch_guest_virt,
 	.read_emulated       = emulator_read_emulated,
 	.write_emulated      = emulator_write_emulated,
@@ -8193,11 +8163,8 @@ static const struct x86_emulate_ops emulate_ops = {
 	.cpl                 = emulator_get_cpl,
 	.get_dr              = emulator_get_dr,
 	.set_dr              = emulator_set_dr,
-	.get_smbase          = emulator_get_smbase,
-	.set_smbase          = emulator_set_smbase,
 	.set_msr_with_filter = emulator_set_msr_with_filter,
 	.get_msr_with_filter = emulator_get_msr_with_filter,
-	.set_msr             = emulator_set_msr,
 	.get_msr             = emulator_get_msr,
 	.check_pmc	     = emulator_check_pmc,
 	.read_pmc            = emulator_read_pmc,
-- 
2.31.1



^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH 05/10] KVM: allow compiling out SMM support
  2022-10-27 16:49 [PATCH v3 0/10] KVM: x86: allow compiling out SMM support Paolo Bonzini
                   ` (3 preceding siblings ...)
  2022-10-27 16:49 ` [PATCH 04/10] KVM: x86: do not go through ctxt->ops when emulating rsm Paolo Bonzini
@ 2022-10-27 16:49 ` Paolo Bonzini
  2022-10-27 16:49 ` [PATCH 06/10] KVM: x86: compile out vendor-specific code if SMM is disabled Paolo Bonzini
                   ` (4 subsequent siblings)
  9 siblings, 0 replies; 12+ messages in thread
From: Paolo Bonzini @ 2022-10-27 16:49 UTC (permalink / raw)
  To: linux-kernel, kvm; +Cc: mlevitsk, seanjc

Some users of KVM implement the UEFI variable store through a paravirtual device
that does not require the "SMM lockbox" component of edk2; allow them to
compile out system management mode, which is not a full implementation
especially in how it interacts with nested virtualization.

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220929172016.319443-6-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/kvm/Kconfig                          | 11 ++++++++++
 arch/x86/kvm/Makefile                         |  2 +-
 arch/x86/kvm/smm.h                            | 12 ++++++++++
 arch/x86/kvm/svm/svm.c                        |  2 ++
 arch/x86/kvm/vmx/vmx.c                        |  2 ++
 arch/x86/kvm/x86.c                            | 22 +++++++++++++++++--
 tools/testing/selftests/kvm/x86_64/smm_test.c |  2 ++
 7 files changed, 50 insertions(+), 3 deletions(-)

diff --git a/arch/x86/kvm/Kconfig b/arch/x86/kvm/Kconfig
index 67be7f217e37..fbeaa9ddef59 100644
--- a/arch/x86/kvm/Kconfig
+++ b/arch/x86/kvm/Kconfig
@@ -118,6 +118,17 @@ config KVM_AMD_SEV
 	  Provides support for launching Encrypted VMs (SEV) and Encrypted VMs
 	  with Encrypted State (SEV-ES) on AMD processors.
 
+config KVM_SMM
+	bool "System Management Mode emulation"
+	default y
+	depends on KVM
+	help
+	  Provides support for KVM to emulate System Management Mode (SMM)
+	  in virtual machines.  This can be used by the virtual machine
+	  firmware to implement UEFI secure boot.
+
+	  If unsure, say Y.
+
 config KVM_XEN
 	bool "Support for Xen hypercall interface"
 	depends on KVM
diff --git a/arch/x86/kvm/Makefile b/arch/x86/kvm/Makefile
index ec6f7656254b..6cf40f668277 100644
--- a/arch/x86/kvm/Makefile
+++ b/arch/x86/kvm/Makefile
@@ -20,7 +20,7 @@ endif
 
 kvm-$(CONFIG_X86_64) += mmu/tdp_iter.o mmu/tdp_mmu.o
 kvm-$(CONFIG_KVM_XEN)	+= xen.o
-kvm-y			+= smm.o
+kvm-$(CONFIG_KVM_SMM)	+= smm.o
 
 kvm-intel-y		+= vmx/vmx.o vmx/vmenter.o vmx/pmu_intel.o vmx/vmcs12.o \
 			   vmx/evmcs.o vmx/nested.o vmx/posted_intr.o
diff --git a/arch/x86/kvm/smm.h b/arch/x86/kvm/smm.h
index b0602a92e511..0e1bd8bd6dc4 100644
--- a/arch/x86/kvm/smm.h
+++ b/arch/x86/kvm/smm.h
@@ -8,6 +8,7 @@
 #define PUT_SMSTATE(type, buf, offset, val)                      \
 	*(type *)((buf) + (offset) - 0x7e00) = val
 
+#ifdef CONFIG_KVM_SMM
 static inline int kvm_inject_smi(struct kvm_vcpu *vcpu)
 {
 	kvm_make_request(KVM_REQ_SMI, vcpu);
@@ -23,5 +24,16 @@ void kvm_smm_changed(struct kvm_vcpu *vcpu, bool in_smm);
 void enter_smm(struct kvm_vcpu *vcpu);
 int emulator_leave_smm(struct x86_emulate_ctxt *ctxt);
 void process_smi(struct kvm_vcpu *vcpu);
+#else
+static inline int kvm_inject_smi(struct kvm_vcpu *vcpu) { return -ENOTTY; }
+static inline bool is_smm(struct kvm_vcpu *vcpu) { return false; }
+static inline void enter_smm(struct kvm_vcpu *vcpu) { WARN_ON_ONCE(1); }
+static inline void process_smi(struct kvm_vcpu *vcpu) { WARN_ON_ONCE(1); }
+
+/*
+ * emulator_leave_smm is used as a function pointer, so the
+ * stub is defined in x86.c.
+ */
+#endif
 
 #endif
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 496ee7d1ae2f..6f7ceb35d2ff 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4150,6 +4150,8 @@ static bool svm_has_emulated_msr(struct kvm *kvm, u32 index)
 	case MSR_IA32_VMX_BASIC ... MSR_IA32_VMX_VMFUNC:
 		return false;
 	case MSR_IA32_SMBASE:
+		if (!IS_ENABLED(CONFIG_KVM_SMM))
+			return false;
 		/* SEV-ES guests do not support SMM, so report false */
 		if (kvm && sev_es_guest(kvm))
 			return false;
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index b459ddf30abd..c2abe62d7cc0 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -6841,6 +6841,8 @@ static bool vmx_has_emulated_msr(struct kvm *kvm, u32 index)
 {
 	switch (index) {
 	case MSR_IA32_SMBASE:
+		if (!IS_ENABLED(CONFIG_KVM_SMM))
+			return false;
 		/*
 		 * We cannot do SMM unless we can run the guest in big
 		 * real mode.
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index ec5e9a837a12..3ec3d3632316 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3641,7 +3641,7 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 		break;
 	}
 	case MSR_IA32_SMBASE:
-		if (!msr_info->host_initiated)
+		if (!IS_ENABLED(CONFIG_KVM_SMM) || !msr_info->host_initiated)
 			return 1;
 		vcpu->arch.smbase = data;
 		break;
@@ -4057,7 +4057,7 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 		msr_info->data = vcpu->arch.ia32_misc_enable_msr;
 		break;
 	case MSR_IA32_SMBASE:
-		if (!msr_info->host_initiated)
+		if (!IS_ENABLED(CONFIG_KVM_SMM) || !msr_info->host_initiated)
 			return 1;
 		msr_info->data = vcpu->arch.smbase;
 		break;
@@ -4431,6 +4431,9 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext)
 			r |= KVM_X86_DISABLE_EXITS_MWAIT;
 		break;
 	case KVM_CAP_X86_SMM:
+		if (!IS_ENABLED(CONFIG_KVM_SMM))
+			break;
+
 		/* SMBASE is usually relocated above 1M on modern chipsets,
 		 * and SMM handlers might indeed rely on 4G segment limits,
 		 * so do not report SMM to be available if real mode is
@@ -5181,6 +5184,7 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
 		vcpu->arch.apic->sipi_vector = events->sipi_vector;
 
 	if (events->flags & KVM_VCPUEVENT_VALID_SMM) {
+#ifdef CONFIG_KVM_SMM
 		if (!!(vcpu->arch.hflags & HF_SMM_MASK) != events->smi.smm) {
 			kvm_x86_ops.nested_ops->leave_nested(vcpu);
 			kvm_smm_changed(vcpu, events->smi.smm);
@@ -5195,6 +5199,12 @@ static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
 				vcpu->arch.hflags &= ~HF_SMM_INSIDE_NMI_MASK;
 		}
 
+#else
+		if (events->smi.smm || events->smi.pending ||
+		    events->smi.smm_inside_nmi)
+			return -EINVAL;
+#endif
+
 		if (lapic_in_kernel(vcpu)) {
 			if (events->smi.latched_init)
 				set_bit(KVM_APIC_INIT, &vcpu->arch.apic->pending_events);
@@ -8120,6 +8130,14 @@ static unsigned emulator_get_hflags(struct x86_emulate_ctxt *ctxt)
 	return emul_to_vcpu(ctxt)->arch.hflags;
 }
 
+#ifndef CONFIG_KVM_SMM
+static int emulator_leave_smm(struct x86_emulate_ctxt *ctxt)
+{
+	WARN_ON_ONCE(1);
+	return X86EMUL_UNHANDLEABLE;
+}
+#endif
+
 static void emulator_triple_fault(struct x86_emulate_ctxt *ctxt)
 {
 	kvm_make_request(KVM_REQ_TRIPLE_FAULT, emul_to_vcpu(ctxt));
diff --git a/tools/testing/selftests/kvm/x86_64/smm_test.c b/tools/testing/selftests/kvm/x86_64/smm_test.c
index 1f136a81858e..cb38a478e1f6 100644
--- a/tools/testing/selftests/kvm/x86_64/smm_test.c
+++ b/tools/testing/selftests/kvm/x86_64/smm_test.c
@@ -137,6 +137,8 @@ int main(int argc, char *argv[])
 	struct kvm_x86_state *state;
 	int stage, stage_reported;
 
+	TEST_REQUIRE(kvm_has_cap(KVM_CAP_X86_SMM));
+
 	/* Create VM */
 	vm = vm_create_with_one_vcpu(&vcpu, guest_code);
 
-- 
2.31.1



^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH 06/10] KVM: x86: compile out vendor-specific code if SMM is disabled
  2022-10-27 16:49 [PATCH v3 0/10] KVM: x86: allow compiling out SMM support Paolo Bonzini
                   ` (4 preceding siblings ...)
  2022-10-27 16:49 ` [PATCH 05/10] KVM: allow compiling out SMM support Paolo Bonzini
@ 2022-10-27 16:49 ` Paolo Bonzini
  2022-10-27 16:49 ` [PATCH 07/10] KVM: x86: remove SMRAM address space if SMM is not supported Paolo Bonzini
                   ` (3 subsequent siblings)
  9 siblings, 0 replies; 12+ messages in thread
From: Paolo Bonzini @ 2022-10-27 16:49 UTC (permalink / raw)
  To: linux-kernel, kvm; +Cc: mlevitsk, seanjc

Vendor-specific code that deals with SMI injection and saving/restoring
SMM state is not needed if CONFIG_KVM_SMM is disabled, so remove the
four callbacks smi_allowed, enter_smm, leave_smm and enable_smi_window.
The users in svm/nested.c and x86.c also have to be compiled out; the
amount of #ifdef'ed code is small and it's not worth moving it to
smm.c.

enter_smm is now used only within #ifdef CONFIG_KVM_SMM, and the stub
can therefore be removed.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220929172016.319443-7-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/include/asm/kvm-x86-ops.h | 2 ++
 arch/x86/include/asm/kvm_host.h    | 2 ++
 arch/x86/kvm/smm.h                 | 1 -
 arch/x86/kvm/svm/nested.c          | 2 ++
 arch/x86/kvm/svm/svm.c             | 4 ++++
 arch/x86/kvm/vmx/vmx.c             | 4 ++++
 arch/x86/kvm/x86.c                 | 4 ++++
 7 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/kvm-x86-ops.h b/arch/x86/include/asm/kvm-x86-ops.h
index 82ba4a564e58..ea58e67e9a67 100644
--- a/arch/x86/include/asm/kvm-x86-ops.h
+++ b/arch/x86/include/asm/kvm-x86-ops.h
@@ -110,10 +110,12 @@ KVM_X86_OP_OPTIONAL_RET0(dy_apicv_has_pending_interrupt)
 KVM_X86_OP_OPTIONAL(set_hv_timer)
 KVM_X86_OP_OPTIONAL(cancel_hv_timer)
 KVM_X86_OP(setup_mce)
+#ifdef CONFIG_KVM_SMM
 KVM_X86_OP(smi_allowed)
 KVM_X86_OP(enter_smm)
 KVM_X86_OP(leave_smm)
 KVM_X86_OP(enable_smi_window)
+#endif
 KVM_X86_OP_OPTIONAL(mem_enc_ioctl)
 KVM_X86_OP_OPTIONAL(mem_enc_register_region)
 KVM_X86_OP_OPTIONAL(mem_enc_unregister_region)
diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 38451bf71b80..fe3ab5df6555 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1607,10 +1607,12 @@ struct kvm_x86_ops {
 
 	void (*setup_mce)(struct kvm_vcpu *vcpu);
 
+#ifdef CONFIG_KVM_SMM
 	int (*smi_allowed)(struct kvm_vcpu *vcpu, bool for_injection);
 	int (*enter_smm)(struct kvm_vcpu *vcpu, char *smstate);
 	int (*leave_smm)(struct kvm_vcpu *vcpu, const char *smstate);
 	void (*enable_smi_window)(struct kvm_vcpu *vcpu);
+#endif
 
 	int (*mem_enc_ioctl)(struct kvm *kvm, void __user *argp);
 	int (*mem_enc_register_region)(struct kvm *kvm, struct kvm_enc_region *argp);
diff --git a/arch/x86/kvm/smm.h b/arch/x86/kvm/smm.h
index 0e1bd8bd6dc4..8debe81494c6 100644
--- a/arch/x86/kvm/smm.h
+++ b/arch/x86/kvm/smm.h
@@ -27,7 +27,6 @@ void process_smi(struct kvm_vcpu *vcpu);
 #else
 static inline int kvm_inject_smi(struct kvm_vcpu *vcpu) { return -ENOTTY; }
 static inline bool is_smm(struct kvm_vcpu *vcpu) { return false; }
-static inline void enter_smm(struct kvm_vcpu *vcpu) { WARN_ON_ONCE(1); }
 static inline void process_smi(struct kvm_vcpu *vcpu) { WARN_ON_ONCE(1); }
 
 /*
diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c
index cc0fd75f7cba..b258d6988f5d 100644
--- a/arch/x86/kvm/svm/nested.c
+++ b/arch/x86/kvm/svm/nested.c
@@ -1378,6 +1378,7 @@ static int svm_check_nested_events(struct kvm_vcpu *vcpu)
 		return 0;
 	}
 
+#ifdef CONFIG_KVM_SMM
 	if (vcpu->arch.smi_pending && !svm_smi_blocked(vcpu)) {
 		if (block_nested_events)
 			return -EBUSY;
@@ -1386,6 +1387,7 @@ static int svm_check_nested_events(struct kvm_vcpu *vcpu)
 		nested_svm_simple_vmexit(svm, SVM_EXIT_SMI);
 		return 0;
 	}
+#endif
 
 	if (vcpu->arch.nmi_pending && !svm_nmi_blocked(vcpu)) {
 		if (block_nested_events)
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 6f7ceb35d2ff..2200b8aa7273 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4408,6 +4408,7 @@ static void svm_setup_mce(struct kvm_vcpu *vcpu)
 	vcpu->arch.mcg_cap &= 0x1ff;
 }
 
+#ifdef CONFIG_KVM_SMM
 bool svm_smi_blocked(struct kvm_vcpu *vcpu)
 {
 	struct vcpu_svm *svm = to_svm(vcpu);
@@ -4557,6 +4558,7 @@ static void svm_enable_smi_window(struct kvm_vcpu *vcpu)
 		/* We must be in SMM; RSM will cause a vmexit anyway.  */
 	}
 }
+#endif
 
 static bool svm_can_emulate_instruction(struct kvm_vcpu *vcpu, int emul_type,
 					void *insn, int insn_len)
@@ -4832,10 +4834,12 @@ static struct kvm_x86_ops svm_x86_ops __initdata = {
 	.pi_update_irte = avic_pi_update_irte,
 	.setup_mce = svm_setup_mce,
 
+#ifdef CONFIG_KVM_SMM
 	.smi_allowed = svm_smi_allowed,
 	.enter_smm = svm_enter_smm,
 	.leave_smm = svm_leave_smm,
 	.enable_smi_window = svm_enable_smi_window,
+#endif
 
 	.mem_enc_ioctl = sev_mem_enc_ioctl,
 	.mem_enc_register_region = sev_mem_enc_register_region,
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index c2abe62d7cc0..ee2f51a886d9 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7905,6 +7905,7 @@ static void vmx_setup_mce(struct kvm_vcpu *vcpu)
 			~FEAT_CTL_LMCE_ENABLED;
 }
 
+#ifdef CONFIG_KVM_SMM
 static int vmx_smi_allowed(struct kvm_vcpu *vcpu, bool for_injection)
 {
 	/* we need a nested vmexit to enter SMM, postpone if run is pending */
@@ -7959,6 +7960,7 @@ static void vmx_enable_smi_window(struct kvm_vcpu *vcpu)
 {
 	/* RSM will cause a vmexit anyway.  */
 }
+#endif
 
 static bool vmx_apic_init_signal_blocked(struct kvm_vcpu *vcpu)
 {
@@ -8126,10 +8128,12 @@ static struct kvm_x86_ops vmx_x86_ops __initdata = {
 
 	.setup_mce = vmx_setup_mce,
 
+#ifdef CONFIG_KVM_SMM
 	.smi_allowed = vmx_smi_allowed,
 	.enter_smm = vmx_enter_smm,
 	.leave_smm = vmx_leave_smm,
 	.enable_smi_window = vmx_enable_smi_window,
+#endif
 
 	.can_emulate_instruction = vmx_can_emulate_instruction,
 	.apic_init_signal_blocked = vmx_apic_init_signal_blocked,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 3ec3d3632316..3f380fb4ed7a 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -9918,6 +9918,7 @@ static int kvm_check_and_inject_events(struct kvm_vcpu *vcpu,
 	 * in order to make progress and get back here for another iteration.
 	 * The kvm_x86_ops hooks communicate this by returning -EBUSY.
 	 */
+#ifdef CONFIG_KVM_SMM
 	if (vcpu->arch.smi_pending) {
 		r = can_inject ? static_call(kvm_x86_smi_allowed)(vcpu, true) : -EBUSY;
 		if (r < 0)
@@ -9930,6 +9931,7 @@ static int kvm_check_and_inject_events(struct kvm_vcpu *vcpu,
 		} else
 			static_call(kvm_x86_enable_smi_window)(vcpu);
 	}
+#endif
 
 	if (vcpu->arch.nmi_pending) {
 		r = can_inject ? static_call(kvm_x86_nmi_allowed)(vcpu, true) : -EBUSY;
@@ -12574,10 +12576,12 @@ static inline bool kvm_vcpu_has_events(struct kvm_vcpu *vcpu)
 	     static_call(kvm_x86_nmi_allowed)(vcpu, false)))
 		return true;
 
+#ifdef CONFIG_KVM_SMM
 	if (kvm_test_request(KVM_REQ_SMI, vcpu) ||
 	    (vcpu->arch.smi_pending &&
 	     static_call(kvm_x86_smi_allowed)(vcpu, false)))
 		return true;
+#endif
 
 	if (kvm_arch_interrupt_allowed(vcpu) &&
 	    (kvm_cpu_has_interrupt(vcpu) ||
-- 
2.31.1



^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH 07/10] KVM: x86: remove SMRAM address space if SMM is not supported
  2022-10-27 16:49 [PATCH v3 0/10] KVM: x86: allow compiling out SMM support Paolo Bonzini
                   ` (5 preceding siblings ...)
  2022-10-27 16:49 ` [PATCH 06/10] KVM: x86: compile out vendor-specific code if SMM is disabled Paolo Bonzini
@ 2022-10-27 16:49 ` Paolo Bonzini
  2022-10-27 16:49 ` [PATCH 08/10] KVM: x86: do not define KVM_REQ_SMI if SMM disabled Paolo Bonzini
                   ` (2 subsequent siblings)
  9 siblings, 0 replies; 12+ messages in thread
From: Paolo Bonzini @ 2022-10-27 16:49 UTC (permalink / raw)
  To: linux-kernel, kvm; +Cc: mlevitsk, seanjc

If CONFIG_KVM_SMM is not defined HF_SMM_MASK will always be zero, and
we can spare userspace the hassle of setting up the SMRAM address space
simply by reporting that only one address space is supported.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220929172016.319443-8-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/include/asm/kvm_host.h | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index fe3ab5df6555..3d8fcded51bb 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1993,11 +1993,14 @@ enum {
 #define HF_SMM_MASK		(1 << 6)
 #define HF_SMM_INSIDE_NMI_MASK	(1 << 7)
 
-#define __KVM_VCPU_MULTIPLE_ADDRESS_SPACE
-#define KVM_ADDRESS_SPACE_NUM 2
-
-#define kvm_arch_vcpu_memslots_id(vcpu) ((vcpu)->arch.hflags & HF_SMM_MASK ? 1 : 0)
-#define kvm_memslots_for_spte_role(kvm, role) __kvm_memslots(kvm, (role).smm)
+#ifdef CONFIG_KVM_SMM
+# define __KVM_VCPU_MULTIPLE_ADDRESS_SPACE
+# define KVM_ADDRESS_SPACE_NUM 2
+# define kvm_arch_vcpu_memslots_id(vcpu) ((vcpu)->arch.hflags & HF_SMM_MASK ? 1 : 0)
+# define kvm_memslots_for_spte_role(kvm, role) __kvm_memslots(kvm, (role).smm)
+#else
+# define kvm_memslots_for_spte_role(kvm, role) __kvm_memslots(kvm, 0)
+#endif
 
 #define KVM_ARCH_WANT_MMU_NOTIFIER
 
-- 
2.31.1



^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH 08/10] KVM: x86: do not define KVM_REQ_SMI if SMM disabled
  2022-10-27 16:49 [PATCH v3 0/10] KVM: x86: allow compiling out SMM support Paolo Bonzini
                   ` (6 preceding siblings ...)
  2022-10-27 16:49 ` [PATCH 07/10] KVM: x86: remove SMRAM address space if SMM is not supported Paolo Bonzini
@ 2022-10-27 16:49 ` Paolo Bonzini
  2022-10-27 16:49 ` [PATCH 09/10] KVM: zero output of KVM_GET_VCPU_EVENTS before filling in the struct Paolo Bonzini
  2022-10-27 16:49 ` [PATCH 10/10] KVM: x86: do not define SMM-related constants if SMM disabled Paolo Bonzini
  9 siblings, 0 replies; 12+ messages in thread
From: Paolo Bonzini @ 2022-10-27 16:49 UTC (permalink / raw)
  To: linux-kernel, kvm; +Cc: mlevitsk, seanjc

This ensures that all the relevant code is compiled out, in fact
the process_smi stub can be removed too.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Reviewed-by: Maxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20220929172016.319443-9-pbonzini@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/include/asm/kvm_host.h | 2 ++
 arch/x86/kvm/smm.h              | 1 -
 arch/x86/kvm/x86.c              | 6 ++++++
 3 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 3d8fcded51bb..7ddcc0e6fae5 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -81,7 +81,9 @@
 #define KVM_REQ_NMI			KVM_ARCH_REQ(9)
 #define KVM_REQ_PMU			KVM_ARCH_REQ(10)
 #define KVM_REQ_PMI			KVM_ARCH_REQ(11)
+#ifdef CONFIG_KVM_SMM
 #define KVM_REQ_SMI			KVM_ARCH_REQ(12)
+#endif
 #define KVM_REQ_MASTERCLOCK_UPDATE	KVM_ARCH_REQ(13)
 #define KVM_REQ_MCLOCK_INPROGRESS \
 	KVM_ARCH_REQ_FLAGS(14, KVM_REQUEST_WAIT | KVM_REQUEST_NO_WAKEUP)
diff --git a/arch/x86/kvm/smm.h b/arch/x86/kvm/smm.h
index 8debe81494c6..53c81394ebdb 100644
--- a/arch/x86/kvm/smm.h
+++ b/arch/x86/kvm/smm.h
@@ -27,7 +27,6 @@ void process_smi(struct kvm_vcpu *vcpu);
 #else
 static inline int kvm_inject_smi(struct kvm_vcpu *vcpu) { return -ENOTTY; }
 static inline bool is_smm(struct kvm_vcpu *vcpu) { return false; }
-static inline void process_smi(struct kvm_vcpu *vcpu) { WARN_ON_ONCE(1); }
 
 /*
  * emulator_leave_smm is used as a function pointer, so the
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 3f380fb4ed7a..f6adb4145759 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5025,8 +5025,10 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu,
 
 	process_nmi(vcpu);
 
+#ifdef CONFIG_KVM_SMM
 	if (kvm_check_request(KVM_REQ_SMI, vcpu))
 		process_smi(vcpu);
+#endif
 
 	/*
 	 * KVM's ABI only allows for one exception to be migrated.  Luckily,
@@ -10262,8 +10264,10 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
 		}
 		if (kvm_check_request(KVM_REQ_STEAL_UPDATE, vcpu))
 			record_steal_time(vcpu);
+#ifdef CONFIG_KVM_SMM
 		if (kvm_check_request(KVM_REQ_SMI, vcpu))
 			process_smi(vcpu);
+#endif
 		if (kvm_check_request(KVM_REQ_NMI, vcpu))
 			process_nmi(vcpu);
 		if (kvm_check_request(KVM_REQ_PMU, vcpu))
@@ -12622,7 +12626,9 @@ bool kvm_arch_dy_runnable(struct kvm_vcpu *vcpu)
 		return true;
 
 	if (kvm_test_request(KVM_REQ_NMI, vcpu) ||
+#ifdef CONFIG_KVM_SMM
 		kvm_test_request(KVM_REQ_SMI, vcpu) ||
+#endif
 		 kvm_test_request(KVM_REQ_EVENT, vcpu))
 		return true;
 
-- 
2.31.1



^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH 09/10] KVM: zero output of KVM_GET_VCPU_EVENTS before filling in the struct
  2022-10-27 16:49 [PATCH v3 0/10] KVM: x86: allow compiling out SMM support Paolo Bonzini
                   ` (7 preceding siblings ...)
  2022-10-27 16:49 ` [PATCH 08/10] KVM: x86: do not define KVM_REQ_SMI if SMM disabled Paolo Bonzini
@ 2022-10-27 16:49 ` Paolo Bonzini
  2022-10-27 16:49 ` [PATCH 10/10] KVM: x86: do not define SMM-related constants if SMM disabled Paolo Bonzini
  9 siblings, 0 replies; 12+ messages in thread
From: Paolo Bonzini @ 2022-10-27 16:49 UTC (permalink / raw)
  To: linux-kernel, kvm; +Cc: mlevitsk, seanjc

This allows making some fields optional, as will be the case soon
for SMM-related data.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/kvm/x86.c | 13 ++++---------
 1 file changed, 4 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index f6adb4145759..5959f74c5a0a 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5056,16 +5056,15 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu,
 	    ex->pending && ex->has_payload)
 		kvm_deliver_exception_payload(vcpu, ex);
 
+	memset(events, 0, sizeof(events));
+
 	/*
 	 * The API doesn't provide the instruction length for software
 	 * exceptions, so don't report them. As long as the guest RIP
 	 * isn't advanced, we should expect to encounter the exception
 	 * again.
 	 */
-	if (kvm_exception_is_soft(ex->vector)) {
-		events->exception.injected = 0;
-		events->exception.pending = 0;
-	} else {
+	if (!kvm_exception_is_soft(ex->vector)) {
 		events->exception.injected = ex->injected;
 		events->exception.pending = ex->pending;
 		/*
@@ -5085,15 +5084,13 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu,
 	events->interrupt.injected =
 		vcpu->arch.interrupt.injected && !vcpu->arch.interrupt.soft;
 	events->interrupt.nr = vcpu->arch.interrupt.nr;
-	events->interrupt.soft = 0;
 	events->interrupt.shadow = static_call(kvm_x86_get_interrupt_shadow)(vcpu);
 
 	events->nmi.injected = vcpu->arch.nmi_injected;
 	events->nmi.pending = vcpu->arch.nmi_pending != 0;
 	events->nmi.masked = static_call(kvm_x86_get_nmi_mask)(vcpu);
-	events->nmi.pad = 0;
 
-	events->sipi_vector = 0; /* never valid when reporting to user space */
+	/* events->sipi_vector is never valid when reporting to user space */
 
 	events->smi.smm = is_smm(vcpu);
 	events->smi.pending = vcpu->arch.smi_pending;
@@ -5110,8 +5107,6 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu,
 		events->triple_fault.pending = kvm_test_request(KVM_REQ_TRIPLE_FAULT, vcpu);
 		events->flags |= KVM_VCPUEVENT_VALID_TRIPLE_FAULT;
 	}
-
-	memset(&events->reserved, 0, sizeof(events->reserved));
 }
 
 static int kvm_vcpu_ioctl_x86_set_vcpu_events(struct kvm_vcpu *vcpu,
-- 
2.31.1



^ permalink raw reply related	[flat|nested] 12+ messages in thread

* [PATCH 10/10] KVM: x86: do not define SMM-related constants if SMM disabled
  2022-10-27 16:49 [PATCH v3 0/10] KVM: x86: allow compiling out SMM support Paolo Bonzini
                   ` (8 preceding siblings ...)
  2022-10-27 16:49 ` [PATCH 09/10] KVM: zero output of KVM_GET_VCPU_EVENTS before filling in the struct Paolo Bonzini
@ 2022-10-27 16:49 ` Paolo Bonzini
  9 siblings, 0 replies; 12+ messages in thread
From: Paolo Bonzini @ 2022-10-27 16:49 UTC (permalink / raw)
  To: linux-kernel, kvm; +Cc: mlevitsk, seanjc

Suggested-by: Sean Christopherson <seanjc@google.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
---
 arch/x86/include/asm/kvm_host.h | 3 ++-
 arch/x86/kvm/smm.c              | 3 +++
 arch/x86/kvm/x86.c              | 4 ++--
 3 files changed, 7 insertions(+), 3 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index 7ddcc0e6fae5..89c89c70f74e 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1992,10 +1992,11 @@ enum {
 #define HF_NMI_MASK		(1 << 3)
 #define HF_IRET_MASK		(1 << 4)
 #define HF_GUEST_MASK		(1 << 5) /* VCPU is in guest-mode */
+
+#ifdef CONFIG_KVM_SMM
 #define HF_SMM_MASK		(1 << 6)
 #define HF_SMM_INSIDE_NMI_MASK	(1 << 7)
 
-#ifdef CONFIG_KVM_SMM
 # define __KVM_VCPU_MULTIPLE_ADDRESS_SPACE
 # define KVM_ADDRESS_SPACE_NUM 2
 # define kvm_arch_vcpu_memslots_id(vcpu) ((vcpu)->arch.hflags & HF_SMM_MASK ? 1 : 0)
diff --git a/arch/x86/kvm/smm.c b/arch/x86/kvm/smm.c
index 41ca128478fc..44a8f7e57b77 100644
--- a/arch/x86/kvm/smm.c
+++ b/arch/x86/kvm/smm.c
@@ -10,6 +10,9 @@
 
 void kvm_smm_changed(struct kvm_vcpu *vcpu, bool entering_smm)
 {
+	BUILD_BUG_ON(HF_SMM_MASK != X86EMUL_SMM_MASK);
+	BUILD_BUG_ON(HF_SMM_INSIDE_NMI_MASK != X86EMUL_SMM_INSIDE_NMI_MASK);
+
 	trace_kvm_smm_transition(vcpu->vcpu_id, vcpu->arch.smbase, entering_smm);
 
 	if (entering_smm) {
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 5959f74c5a0a..910e3757b222 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5092,10 +5092,12 @@ static void kvm_vcpu_ioctl_x86_get_vcpu_events(struct kvm_vcpu *vcpu,
 
 	/* events->sipi_vector is never valid when reporting to user space */
 
+#ifdef CONFIG_KVM_SMM
 	events->smi.smm = is_smm(vcpu);
 	events->smi.pending = vcpu->arch.smi_pending;
 	events->smi.smm_inside_nmi =
 		!!(vcpu->arch.hflags & HF_SMM_INSIDE_NMI_MASK);
+#endif
 	events->smi.latched_init = kvm_lapic_latched_init(vcpu);
 
 	events->flags = (KVM_VCPUEVENT_VALID_NMI_PENDING
@@ -8266,8 +8268,6 @@ static void init_emulate_ctxt(struct kvm_vcpu *vcpu)
 		     cs_db				? X86EMUL_MODE_PROT32 :
 							  X86EMUL_MODE_PROT16;
 	BUILD_BUG_ON(HF_GUEST_MASK != X86EMUL_GUEST_MASK);
-	BUILD_BUG_ON(HF_SMM_MASK != X86EMUL_SMM_MASK);
-	BUILD_BUG_ON(HF_SMM_INSIDE_NMI_MASK != X86EMUL_SMM_INSIDE_NMI_MASK);
 
 	ctxt->interruptibility = 0;
 	ctxt->have_exception = false;
-- 
2.31.1


^ permalink raw reply related	[flat|nested] 12+ messages in thread

* Re: [PATCH 04/10] KVM: x86: do not go through ctxt->ops when emulating rsm
       [not found]   ` <202210281538.c5NukqBx-lkp@intel.com>
@ 2022-10-28 21:46     ` Sean Christopherson
  0 siblings, 0 replies; 12+ messages in thread
From: Sean Christopherson @ 2022-10-28 21:46 UTC (permalink / raw)
  To: kernel test robot
  Cc: Paolo Bonzini, linux-kernel, kvm, oe-kbuild-all, mlevitsk

On Fri, Oct 28, 2022, kernel test robot wrote:
> All warnings (new ones prefixed by >>):
> 
>    arch/x86/kvm/smm.c: In function 'emulator_leave_smm':
> >> arch/x86/kvm/smm.c:503:33: warning: unused variable 'efer' [-Wunused-variable]
>      503 |         unsigned long cr0, cr4, efer;
>          |                                 ^~~~
> >> arch/x86/kvm/smm.c:503:28: warning: unused variable 'cr4' [-Wunused-variable]
>      503 |         unsigned long cr0, cr4, efer;
>          |                            ^~~
> 
> 
> vim +/efer +503 arch/x86/kvm/smm.c
> 
> e2881deb76e87c Paolo Bonzini 2022-10-27  499  
> e2881deb76e87c Paolo Bonzini 2022-10-27  500  int emulator_leave_smm(struct x86_emulate_ctxt *ctxt)
> e2881deb76e87c Paolo Bonzini 2022-10-27  501  {
> e2881deb76e87c Paolo Bonzini 2022-10-27  502  	struct kvm_vcpu *vcpu = ctxt->vcpu;
> e2881deb76e87c Paolo Bonzini 2022-10-27 @503  	unsigned long cr0, cr4, efer;
> e2881deb76e87c Paolo Bonzini 2022-10-27  504  	char buf[512];
> e2881deb76e87c Paolo Bonzini 2022-10-27  505  	u64 smbase;
> e2881deb76e87c Paolo Bonzini 2022-10-27  506  	int ret;
> e2881deb76e87c Paolo Bonzini 2022-10-27  507  
> 9842725ac4bb94 Paolo Bonzini 2022-10-27  508  	smbase = vcpu->arch.smbase;
> e2881deb76e87c Paolo Bonzini 2022-10-27  509  
> 9842725ac4bb94 Paolo Bonzini 2022-10-27  510  	ret = kvm_vcpu_read_guest(vcpu, smbase + 0xfe00, buf, sizeof(buf));
> 9842725ac4bb94 Paolo Bonzini 2022-10-27  511  	if (ret < 0)
> e2881deb76e87c Paolo Bonzini 2022-10-27  512  		return X86EMUL_UNHANDLEABLE;
> e2881deb76e87c Paolo Bonzini 2022-10-27  513  
> 9842725ac4bb94 Paolo Bonzini 2022-10-27  514  	if ((vcpu->arch.hflags & HF_SMM_INSIDE_NMI_MASK) == 0)
> 9842725ac4bb94 Paolo Bonzini 2022-10-27  515  		static_call(kvm_x86_set_nmi_mask)(vcpu, false);
> e2881deb76e87c Paolo Bonzini 2022-10-27  516  
> e2881deb76e87c Paolo Bonzini 2022-10-27  517  	kvm_smm_changed(vcpu, false);
> e2881deb76e87c Paolo Bonzini 2022-10-27  518  
> e2881deb76e87c Paolo Bonzini 2022-10-27  519  	/*
> e2881deb76e87c Paolo Bonzini 2022-10-27  520  	 * Get back to real mode, to prepare a safe state in which to load
> e2881deb76e87c Paolo Bonzini 2022-10-27  521  	 * CR0/CR3/CR4/EFER.  It's all a bit more complicated if the vCPU
> e2881deb76e87c Paolo Bonzini 2022-10-27  522  	 * supports long mode.
> e2881deb76e87c Paolo Bonzini 2022-10-27  523  	 */
> 9842725ac4bb94 Paolo Bonzini 2022-10-27  524  #ifdef CONFIG_X86_64
> 9842725ac4bb94 Paolo Bonzini 2022-10-27  525  	if (guest_cpuid_has(vcpu, X86_FEATURE_LM)) {

My suggestion from the previous version[*] should still work.  Copy+pasted below
for convenience, may or may not apply cleanly.

https://lore.kernel.org/all/Y0nO0quQnVFQruPM@google.com

---
 arch/x86/kvm/smm.c | 12 +++++-------
 1 file changed, 5 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kvm/smm.c b/arch/x86/kvm/smm.c
index 41ca128478fc..740fca1cf3a3 100644
--- a/arch/x86/kvm/smm.c
+++ b/arch/x86/kvm/smm.c
@@ -500,6 +500,8 @@ static int rsm_load_state_64(struct x86_emulate_ctxt *ctxt,
 int emulator_leave_smm(struct x86_emulate_ctxt *ctxt)
 {
 	struct kvm_vcpu *vcpu = ctxt->vcpu;
+	bool is_64bit_vcpu = IS_ENABLED(CONFIG_X86_64) &&
+			     guest_cpuid_has(vcpu, X86_FEATURE_LM);
 	unsigned long cr0, cr4, efer;
 	char buf[512];
 	u64 smbase;
@@ -521,8 +523,7 @@ int emulator_leave_smm(struct x86_emulate_ctxt *ctxt)
 	 * CR0/CR3/CR4/EFER.  It's all a bit more complicated if the vCPU
 	 * supports long mode.
 	 */
-#ifdef CONFIG_X86_64
-	if (guest_cpuid_has(vcpu, X86_FEATURE_LM)) {
+	if (is_64bit_vcpu) {
 		struct kvm_segment cs_desc;
 
 		/* Zero CR4.PCIDE before CR0.PG.  */
@@ -536,15 +537,13 @@ int emulator_leave_smm(struct x86_emulate_ctxt *ctxt)
 		cs_desc.s = cs_desc.g = cs_desc.present = 1;
 		kvm_set_segment(vcpu, &cs_desc, VCPU_SREG_CS);
 	}
-#endif
 
 	/* For the 64-bit case, this will clear EFER.LMA.  */
 	cr0 = kvm_read_cr0(vcpu);
 	if (cr0 & X86_CR0_PE)
 		kvm_set_cr0(vcpu, cr0 & ~(X86_CR0_PG | X86_CR0_PE));
 
-#ifdef CONFIG_X86_64
-	if (guest_cpuid_has(vcpu, X86_FEATURE_LM)) {
+	if (is_64bit_vcpu) {
 		/* Clear CR4.PAE before clearing EFER.LME. */
 		cr4 = kvm_read_cr4(vcpu);
 		if (cr4 & X86_CR4_PAE)
@@ -554,7 +553,6 @@ int emulator_leave_smm(struct x86_emulate_ctxt *ctxt)
 		efer = 0;
 		kvm_set_msr(vcpu, MSR_EFER, efer);
 	}
-#endif
 
 	/*
 	 * Give leave_smm() a chance to make ISA-specific changes to the vCPU
@@ -565,7 +563,7 @@ int emulator_leave_smm(struct x86_emulate_ctxt *ctxt)
 		return X86EMUL_UNHANDLEABLE;
 
 #ifdef CONFIG_X86_64
-	if (guest_cpuid_has(vcpu, X86_FEATURE_LM))
+	if (is_64bit_vcpu)
 		return rsm_load_state_64(ctxt, buf);
 	else
 #endif

base-commit: 8b86d27cc60a150252b04989de818ad4ec85f899
-- 

^ permalink raw reply related	[flat|nested] 12+ messages in thread

end of thread, other threads:[~2022-10-28 21:46 UTC | newest]

Thread overview: 12+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2022-10-27 16:49 [PATCH v3 0/10] KVM: x86: allow compiling out SMM support Paolo Bonzini
2022-10-27 16:49 ` [PATCH 01/10] KVM: x86: start moving SMM-related functions to new files Paolo Bonzini
2022-10-27 16:49 ` [PATCH 02/10] KVM: x86: move SMM entry to a new file Paolo Bonzini
2022-10-27 16:49 ` [PATCH 03/10] KVM: x86: move SMM exit " Paolo Bonzini
2022-10-27 16:49 ` [PATCH 04/10] KVM: x86: do not go through ctxt->ops when emulating rsm Paolo Bonzini
     [not found]   ` <202210281538.c5NukqBx-lkp@intel.com>
2022-10-28 21:46     ` Sean Christopherson
2022-10-27 16:49 ` [PATCH 05/10] KVM: allow compiling out SMM support Paolo Bonzini
2022-10-27 16:49 ` [PATCH 06/10] KVM: x86: compile out vendor-specific code if SMM is disabled Paolo Bonzini
2022-10-27 16:49 ` [PATCH 07/10] KVM: x86: remove SMRAM address space if SMM is not supported Paolo Bonzini
2022-10-27 16:49 ` [PATCH 08/10] KVM: x86: do not define KVM_REQ_SMI if SMM disabled Paolo Bonzini
2022-10-27 16:49 ` [PATCH 09/10] KVM: zero output of KVM_GET_VCPU_EVENTS before filling in the struct Paolo Bonzini
2022-10-27 16:49 ` [PATCH 10/10] KVM: x86: do not define SMM-related constants if SMM disabled Paolo Bonzini

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